Solutions to $a (2 a^2 + 2 b^2 + c^2 + d^2) = (2 a^3 + 2 b^3 + c^3 + d^3)$ in integers
$begingroup$
I ask for positive integral solutions to $a (2 a^2 + 2 b^2 + c^2 + d^2) = (2 a^3 + 2 b^3 + c^3 + d^3)$, where a,b,c,d are positive integers and $aneq bneq cneq d$.
In particular does a solution exist for $d>1$.
number-theory
$endgroup$
add a comment |
$begingroup$
I ask for positive integral solutions to $a (2 a^2 + 2 b^2 + c^2 + d^2) = (2 a^3 + 2 b^3 + c^3 + d^3)$, where a,b,c,d are positive integers and $aneq bneq cneq d$.
In particular does a solution exist for $d>1$.
number-theory
$endgroup$
$begingroup$
Would you append an update to this instead of duplication?
$endgroup$
– metamorphy
Jan 5 at 18:52
$begingroup$
@metamorphy it is not a duplication
$endgroup$
– user631773
Jan 5 at 18:53
$begingroup$
Very similar to ... math.stackexchange.com/questions/3062146/…
$endgroup$
– Donald Splutterwit
Jan 5 at 19:11
add a comment |
$begingroup$
I ask for positive integral solutions to $a (2 a^2 + 2 b^2 + c^2 + d^2) = (2 a^3 + 2 b^3 + c^3 + d^3)$, where a,b,c,d are positive integers and $aneq bneq cneq d$.
In particular does a solution exist for $d>1$.
number-theory
$endgroup$
I ask for positive integral solutions to $a (2 a^2 + 2 b^2 + c^2 + d^2) = (2 a^3 + 2 b^3 + c^3 + d^3)$, where a,b,c,d are positive integers and $aneq bneq cneq d$.
In particular does a solution exist for $d>1$.
number-theory
number-theory
asked Jan 5 at 18:49
user631773user631773
11
11
$begingroup$
Would you append an update to this instead of duplication?
$endgroup$
– metamorphy
Jan 5 at 18:52
$begingroup$
@metamorphy it is not a duplication
$endgroup$
– user631773
Jan 5 at 18:53
$begingroup$
Very similar to ... math.stackexchange.com/questions/3062146/…
$endgroup$
– Donald Splutterwit
Jan 5 at 19:11
add a comment |
$begingroup$
Would you append an update to this instead of duplication?
$endgroup$
– metamorphy
Jan 5 at 18:52
$begingroup$
@metamorphy it is not a duplication
$endgroup$
– user631773
Jan 5 at 18:53
$begingroup$
Very similar to ... math.stackexchange.com/questions/3062146/…
$endgroup$
– Donald Splutterwit
Jan 5 at 19:11
$begingroup$
Would you append an update to this instead of duplication?
$endgroup$
– metamorphy
Jan 5 at 18:52
$begingroup$
Would you append an update to this instead of duplication?
$endgroup$
– metamorphy
Jan 5 at 18:52
$begingroup$
@metamorphy it is not a duplication
$endgroup$
– user631773
Jan 5 at 18:53
$begingroup$
@metamorphy it is not a duplication
$endgroup$
– user631773
Jan 5 at 18:53
$begingroup$
Very similar to ... math.stackexchange.com/questions/3062146/…
$endgroup$
– Donald Splutterwit
Jan 5 at 19:11
$begingroup$
Very similar to ... math.stackexchange.com/questions/3062146/…
$endgroup$
– Donald Splutterwit
Jan 5 at 19:11
add a comment |
2 Answers
2
active
oldest
votes
$begingroup$
Yes, $(5,2,6,2)$ by brute force.
Start by noting that $a = frac{2b^3+c^3+d^3}{2b^2+c^2+d^2}$. Since we want $d>1$, let $ d = 2$.
First try, let $b = 1$. The whole thing simplifies to $a = frac{c^3+10}{c^2+6} = c + frac{10-6c}{c^2+6}$. Now, $c = 1$ won't give integer. For $c > 2$, if $a$ is integer, then $|10-6c|geq c^2 + 6$, i.e. $6c-10geq c^2+6$, which has no real solutions. Thus, $a$ is never a positive integer.
Now try $b = 2$. Then, $a = frac{c^3+24}{c^2+12} = c + frac{24-12c}{c^2+12}$. As before, $c = 1$ is not a solution. $c = 2$ is a solution of type $a=b=c=d$. If $c>2$, for $a$ to be an integer, we need $|24-12c|geq c^2+12$. Now, $12c-24 geq c^2+12$ iff $(c-6)^2 leq 0$ iff $c = 6$. One checks that this $c$ gives $a= 5$.
$endgroup$
add a comment |
$begingroup$
take any triple $b,c,d,$ with $gcd(b,c,d)=1,$ there is a smallest $k$ such that $(a,kb,kc,kd)$ is a solution with $a$ integral, while $gcd(a,kb,kc,kd) = 1.$ Also
$$ k = frac{2b^2+c^2+d^2}{gcd left( 2b^2+c^2+d^2 ;, ;2b^3+c^3+d^3 right)} $$
original 1 1 1 mult 1 gives 1 1 1 1
original 1 2 1 mult 7 gives 11 7 14 7
original 1 2 2 mult 5 gives 9 5 10 10
original 1 3 1 mult 2 gives 5 2 6 2
original 1 3 2 mult 15 gives 37 15 45 30
original 1 3 3 mult 5 gives 14 5 15 15
original 1 4 1 mult 19 gives 67 19 76 19
original 1 4 2 mult 11 gives 37 11 44 22
original 1 4 3 mult 9 gives 31 9 36 27
original 1 4 4 mult 17 gives 65 17 68 68
original 1 5 1 mult 7 gives 32 7 35 7
original 1 5 2 mult 31 gives 135 31 155 62
original 1 5 3 mult 18 gives 77 18 90 54
original 1 5 4 mult 43 gives 191 43 215 172
original 1 5 5 mult 13 gives 63 13 65 65
original 1 6 1 mult 13 gives 73 13 78 13
original 1 6 2 mult 21 gives 113 21 126 42
original 1 6 3 mult 47 gives 245 47 282 141
original 1 6 4 mult 9 gives 47 9 54 36
original 1 6 5 mult 9 gives 49 9 54 45
original 1 6 6 mult 37 gives 217 37 222 222
original 2 1 1 mult 5 gives 9 10 5 5
original 2 2 1 mult 13 gives 25 26 26 13
original 2 3 1 mult 9 gives 22 18 27 9
original 2 3 2 mult 7 gives 17 14 21 14
original 2 3 3 mult 13 gives 35 26 39 39
original 2 4 1 mult 25 gives 81 50 100 25
original 2 4 3 mult 33 gives 107 66 132 99
original 2 5 1 mult 17 gives 71 34 85 17
original 2 5 2 mult 37 gives 149 74 185 74
original 2 5 3 mult 1 gives 4 2 5 3
original 2 5 4 mult 49 gives 205 98 245 196
original 2 5 5 mult 29 gives 133 58 145 145
original 2 6 1 mult 45 gives 233 90 270 45
original 2 6 3 mult 53 gives 259 106 318 159
original 2 6 5 mult 23 gives 119 46 138 115
original 3 1 1 mult 5 gives 14 15 5 5
original 3 2 1 mult 23 gives 63 69 46 23
original 3 2 2 mult 13 gives 35 39 26 26
original 3 3 1 mult 14 gives 41 42 42 14
original 3 3 2 mult 31 gives 89 93 93 62
original 3 4 1 mult 5 gives 17 15 20 5
original 3 4 2 mult 19 gives 63 57 76 38
original 3 4 3 mult 43 gives 145 129 172 129
original 3 4 4 mult 25 gives 91 75 100 100
original 3 5 1 mult 11 gives 45 33 55 11
original 3 5 2 mult 47 gives 187 141 235 94
original 3 5 3 mult 26 gives 103 78 130 78
original 3 5 4 mult 59 gives 243 177 295 236
original 3 5 5 mult 17 gives 76 51 85 85
original 3 6 1 mult 55 gives 271 165 330 55
original 3 6 2 mult 29 gives 139 87 174 58
original 3 6 4 mult 35 gives 167 105 210 140
original 3 6 5 mult 1 gives 5 3 6 5
original 4 1 1 mult 17 gives 65 68 17 17
original 4 2 1 mult 37 gives 137 148 74 37
original 4 3 1 mult 7 gives 26 28 21 7
original 4 3 2 mult 45 gives 163 180 135 90
original 4 3 3 mult 25 gives 91 100 75 75
original 4 4 1 mult 49 gives 193 196 196 49
original 4 4 3 mult 19 gives 73 76 76 57
original 4 5 1 mult 29 gives 127 116 145 29
original 4 5 2 mult 61 gives 261 244 305 122
original 4 5 3 mult 33 gives 140 132 165 99
original 4 5 4 mult 73 gives 317 292 365 292
original 4 5 5 mult 41 gives 189 164 205 205
original 4 6 1 mult 1 gives 5 4 6 1
original 4 6 3 mult 11 gives 53 44 66 33
original 4 6 5 mult 93 gives 469 372 558 465
original 5 1 1 mult 13 gives 63 65 13 13
original 5 2 1 mult 55 gives 259 275 110 55
original 5 2 2 mult 29 gives 133 145 58 58
original 5 3 1 mult 30 gives 139 150 90 30
original 5 3 2 mult 21 gives 95 105 63 42
original 5 3 3 mult 17 gives 76 85 51 51
original 5 4 1 mult 67 gives 315 335 268 67
original 5 4 2 mult 5 gives 23 25 20 10
original 5 4 3 mult 75 gives 341 375 300 225
original 5 4 4 mult 41 gives 189 205 164 164
original 5 5 1 mult 19 gives 94 95 95 19
original 5 5 2 mult 79 gives 383 395 395 158
original 5 5 3 mult 14 gives 67 70 70 42
original 5 5 4 mult 91 gives 439 455 455 364
original 5 6 1 mult 87 gives 467 435 522 87
original 5 6 2 mult 15 gives 79 75 90 30
original 5 6 3 mult 95 gives 493 475 570 285
original 5 6 4 mult 51 gives 265 255 306 204
original 5 6 5 mult 37 gives 197 185 222 185
original 5 6 6 mult 61 gives 341 305 366 366
original 6 1 1 mult 37 gives 217 222 37 37
original 6 2 1 mult 11 gives 63 66 22 11
original 6 3 1 mult 41 gives 230 246 123 41
original 6 3 2 mult 85 gives 467 510 255 170
original 6 4 1 mult 89 gives 497 534 356 89
original 6 4 3 mult 97 gives 523 582 388 291
original 6 5 1 mult 49 gives 279 294 245 49
original 6 5 2 mult 101 gives 565 606 505 202
original 6 5 3 mult 53 gives 292 318 265 159
original 6 5 4 mult 113 gives 621 678 565 452
original 6 5 5 mult 61 gives 341 366 305 305
original 6 6 1 mult 109 gives 649 654 654 109
original 6 6 5 mult 133 gives 773 798 798 665
$endgroup$
add a comment |
Your Answer
StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3063069%2fsolutions-to-a-2-a2-2-b2-c2-d2-2-a3-2-b3-c3-d3-in-in%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Yes, $(5,2,6,2)$ by brute force.
Start by noting that $a = frac{2b^3+c^3+d^3}{2b^2+c^2+d^2}$. Since we want $d>1$, let $ d = 2$.
First try, let $b = 1$. The whole thing simplifies to $a = frac{c^3+10}{c^2+6} = c + frac{10-6c}{c^2+6}$. Now, $c = 1$ won't give integer. For $c > 2$, if $a$ is integer, then $|10-6c|geq c^2 + 6$, i.e. $6c-10geq c^2+6$, which has no real solutions. Thus, $a$ is never a positive integer.
Now try $b = 2$. Then, $a = frac{c^3+24}{c^2+12} = c + frac{24-12c}{c^2+12}$. As before, $c = 1$ is not a solution. $c = 2$ is a solution of type $a=b=c=d$. If $c>2$, for $a$ to be an integer, we need $|24-12c|geq c^2+12$. Now, $12c-24 geq c^2+12$ iff $(c-6)^2 leq 0$ iff $c = 6$. One checks that this $c$ gives $a= 5$.
$endgroup$
add a comment |
$begingroup$
Yes, $(5,2,6,2)$ by brute force.
Start by noting that $a = frac{2b^3+c^3+d^3}{2b^2+c^2+d^2}$. Since we want $d>1$, let $ d = 2$.
First try, let $b = 1$. The whole thing simplifies to $a = frac{c^3+10}{c^2+6} = c + frac{10-6c}{c^2+6}$. Now, $c = 1$ won't give integer. For $c > 2$, if $a$ is integer, then $|10-6c|geq c^2 + 6$, i.e. $6c-10geq c^2+6$, which has no real solutions. Thus, $a$ is never a positive integer.
Now try $b = 2$. Then, $a = frac{c^3+24}{c^2+12} = c + frac{24-12c}{c^2+12}$. As before, $c = 1$ is not a solution. $c = 2$ is a solution of type $a=b=c=d$. If $c>2$, for $a$ to be an integer, we need $|24-12c|geq c^2+12$. Now, $12c-24 geq c^2+12$ iff $(c-6)^2 leq 0$ iff $c = 6$. One checks that this $c$ gives $a= 5$.
$endgroup$
add a comment |
$begingroup$
Yes, $(5,2,6,2)$ by brute force.
Start by noting that $a = frac{2b^3+c^3+d^3}{2b^2+c^2+d^2}$. Since we want $d>1$, let $ d = 2$.
First try, let $b = 1$. The whole thing simplifies to $a = frac{c^3+10}{c^2+6} = c + frac{10-6c}{c^2+6}$. Now, $c = 1$ won't give integer. For $c > 2$, if $a$ is integer, then $|10-6c|geq c^2 + 6$, i.e. $6c-10geq c^2+6$, which has no real solutions. Thus, $a$ is never a positive integer.
Now try $b = 2$. Then, $a = frac{c^3+24}{c^2+12} = c + frac{24-12c}{c^2+12}$. As before, $c = 1$ is not a solution. $c = 2$ is a solution of type $a=b=c=d$. If $c>2$, for $a$ to be an integer, we need $|24-12c|geq c^2+12$. Now, $12c-24 geq c^2+12$ iff $(c-6)^2 leq 0$ iff $c = 6$. One checks that this $c$ gives $a= 5$.
$endgroup$
Yes, $(5,2,6,2)$ by brute force.
Start by noting that $a = frac{2b^3+c^3+d^3}{2b^2+c^2+d^2}$. Since we want $d>1$, let $ d = 2$.
First try, let $b = 1$. The whole thing simplifies to $a = frac{c^3+10}{c^2+6} = c + frac{10-6c}{c^2+6}$. Now, $c = 1$ won't give integer. For $c > 2$, if $a$ is integer, then $|10-6c|geq c^2 + 6$, i.e. $6c-10geq c^2+6$, which has no real solutions. Thus, $a$ is never a positive integer.
Now try $b = 2$. Then, $a = frac{c^3+24}{c^2+12} = c + frac{24-12c}{c^2+12}$. As before, $c = 1$ is not a solution. $c = 2$ is a solution of type $a=b=c=d$. If $c>2$, for $a$ to be an integer, we need $|24-12c|geq c^2+12$. Now, $12c-24 geq c^2+12$ iff $(c-6)^2 leq 0$ iff $c = 6$. One checks that this $c$ gives $a= 5$.
answered Jan 5 at 19:25
EnnarEnnar
14.5k32443
14.5k32443
add a comment |
add a comment |
$begingroup$
take any triple $b,c,d,$ with $gcd(b,c,d)=1,$ there is a smallest $k$ such that $(a,kb,kc,kd)$ is a solution with $a$ integral, while $gcd(a,kb,kc,kd) = 1.$ Also
$$ k = frac{2b^2+c^2+d^2}{gcd left( 2b^2+c^2+d^2 ;, ;2b^3+c^3+d^3 right)} $$
original 1 1 1 mult 1 gives 1 1 1 1
original 1 2 1 mult 7 gives 11 7 14 7
original 1 2 2 mult 5 gives 9 5 10 10
original 1 3 1 mult 2 gives 5 2 6 2
original 1 3 2 mult 15 gives 37 15 45 30
original 1 3 3 mult 5 gives 14 5 15 15
original 1 4 1 mult 19 gives 67 19 76 19
original 1 4 2 mult 11 gives 37 11 44 22
original 1 4 3 mult 9 gives 31 9 36 27
original 1 4 4 mult 17 gives 65 17 68 68
original 1 5 1 mult 7 gives 32 7 35 7
original 1 5 2 mult 31 gives 135 31 155 62
original 1 5 3 mult 18 gives 77 18 90 54
original 1 5 4 mult 43 gives 191 43 215 172
original 1 5 5 mult 13 gives 63 13 65 65
original 1 6 1 mult 13 gives 73 13 78 13
original 1 6 2 mult 21 gives 113 21 126 42
original 1 6 3 mult 47 gives 245 47 282 141
original 1 6 4 mult 9 gives 47 9 54 36
original 1 6 5 mult 9 gives 49 9 54 45
original 1 6 6 mult 37 gives 217 37 222 222
original 2 1 1 mult 5 gives 9 10 5 5
original 2 2 1 mult 13 gives 25 26 26 13
original 2 3 1 mult 9 gives 22 18 27 9
original 2 3 2 mult 7 gives 17 14 21 14
original 2 3 3 mult 13 gives 35 26 39 39
original 2 4 1 mult 25 gives 81 50 100 25
original 2 4 3 mult 33 gives 107 66 132 99
original 2 5 1 mult 17 gives 71 34 85 17
original 2 5 2 mult 37 gives 149 74 185 74
original 2 5 3 mult 1 gives 4 2 5 3
original 2 5 4 mult 49 gives 205 98 245 196
original 2 5 5 mult 29 gives 133 58 145 145
original 2 6 1 mult 45 gives 233 90 270 45
original 2 6 3 mult 53 gives 259 106 318 159
original 2 6 5 mult 23 gives 119 46 138 115
original 3 1 1 mult 5 gives 14 15 5 5
original 3 2 1 mult 23 gives 63 69 46 23
original 3 2 2 mult 13 gives 35 39 26 26
original 3 3 1 mult 14 gives 41 42 42 14
original 3 3 2 mult 31 gives 89 93 93 62
original 3 4 1 mult 5 gives 17 15 20 5
original 3 4 2 mult 19 gives 63 57 76 38
original 3 4 3 mult 43 gives 145 129 172 129
original 3 4 4 mult 25 gives 91 75 100 100
original 3 5 1 mult 11 gives 45 33 55 11
original 3 5 2 mult 47 gives 187 141 235 94
original 3 5 3 mult 26 gives 103 78 130 78
original 3 5 4 mult 59 gives 243 177 295 236
original 3 5 5 mult 17 gives 76 51 85 85
original 3 6 1 mult 55 gives 271 165 330 55
original 3 6 2 mult 29 gives 139 87 174 58
original 3 6 4 mult 35 gives 167 105 210 140
original 3 6 5 mult 1 gives 5 3 6 5
original 4 1 1 mult 17 gives 65 68 17 17
original 4 2 1 mult 37 gives 137 148 74 37
original 4 3 1 mult 7 gives 26 28 21 7
original 4 3 2 mult 45 gives 163 180 135 90
original 4 3 3 mult 25 gives 91 100 75 75
original 4 4 1 mult 49 gives 193 196 196 49
original 4 4 3 mult 19 gives 73 76 76 57
original 4 5 1 mult 29 gives 127 116 145 29
original 4 5 2 mult 61 gives 261 244 305 122
original 4 5 3 mult 33 gives 140 132 165 99
original 4 5 4 mult 73 gives 317 292 365 292
original 4 5 5 mult 41 gives 189 164 205 205
original 4 6 1 mult 1 gives 5 4 6 1
original 4 6 3 mult 11 gives 53 44 66 33
original 4 6 5 mult 93 gives 469 372 558 465
original 5 1 1 mult 13 gives 63 65 13 13
original 5 2 1 mult 55 gives 259 275 110 55
original 5 2 2 mult 29 gives 133 145 58 58
original 5 3 1 mult 30 gives 139 150 90 30
original 5 3 2 mult 21 gives 95 105 63 42
original 5 3 3 mult 17 gives 76 85 51 51
original 5 4 1 mult 67 gives 315 335 268 67
original 5 4 2 mult 5 gives 23 25 20 10
original 5 4 3 mult 75 gives 341 375 300 225
original 5 4 4 mult 41 gives 189 205 164 164
original 5 5 1 mult 19 gives 94 95 95 19
original 5 5 2 mult 79 gives 383 395 395 158
original 5 5 3 mult 14 gives 67 70 70 42
original 5 5 4 mult 91 gives 439 455 455 364
original 5 6 1 mult 87 gives 467 435 522 87
original 5 6 2 mult 15 gives 79 75 90 30
original 5 6 3 mult 95 gives 493 475 570 285
original 5 6 4 mult 51 gives 265 255 306 204
original 5 6 5 mult 37 gives 197 185 222 185
original 5 6 6 mult 61 gives 341 305 366 366
original 6 1 1 mult 37 gives 217 222 37 37
original 6 2 1 mult 11 gives 63 66 22 11
original 6 3 1 mult 41 gives 230 246 123 41
original 6 3 2 mult 85 gives 467 510 255 170
original 6 4 1 mult 89 gives 497 534 356 89
original 6 4 3 mult 97 gives 523 582 388 291
original 6 5 1 mult 49 gives 279 294 245 49
original 6 5 2 mult 101 gives 565 606 505 202
original 6 5 3 mult 53 gives 292 318 265 159
original 6 5 4 mult 113 gives 621 678 565 452
original 6 5 5 mult 61 gives 341 366 305 305
original 6 6 1 mult 109 gives 649 654 654 109
original 6 6 5 mult 133 gives 773 798 798 665
$endgroup$
add a comment |
$begingroup$
take any triple $b,c,d,$ with $gcd(b,c,d)=1,$ there is a smallest $k$ such that $(a,kb,kc,kd)$ is a solution with $a$ integral, while $gcd(a,kb,kc,kd) = 1.$ Also
$$ k = frac{2b^2+c^2+d^2}{gcd left( 2b^2+c^2+d^2 ;, ;2b^3+c^3+d^3 right)} $$
original 1 1 1 mult 1 gives 1 1 1 1
original 1 2 1 mult 7 gives 11 7 14 7
original 1 2 2 mult 5 gives 9 5 10 10
original 1 3 1 mult 2 gives 5 2 6 2
original 1 3 2 mult 15 gives 37 15 45 30
original 1 3 3 mult 5 gives 14 5 15 15
original 1 4 1 mult 19 gives 67 19 76 19
original 1 4 2 mult 11 gives 37 11 44 22
original 1 4 3 mult 9 gives 31 9 36 27
original 1 4 4 mult 17 gives 65 17 68 68
original 1 5 1 mult 7 gives 32 7 35 7
original 1 5 2 mult 31 gives 135 31 155 62
original 1 5 3 mult 18 gives 77 18 90 54
original 1 5 4 mult 43 gives 191 43 215 172
original 1 5 5 mult 13 gives 63 13 65 65
original 1 6 1 mult 13 gives 73 13 78 13
original 1 6 2 mult 21 gives 113 21 126 42
original 1 6 3 mult 47 gives 245 47 282 141
original 1 6 4 mult 9 gives 47 9 54 36
original 1 6 5 mult 9 gives 49 9 54 45
original 1 6 6 mult 37 gives 217 37 222 222
original 2 1 1 mult 5 gives 9 10 5 5
original 2 2 1 mult 13 gives 25 26 26 13
original 2 3 1 mult 9 gives 22 18 27 9
original 2 3 2 mult 7 gives 17 14 21 14
original 2 3 3 mult 13 gives 35 26 39 39
original 2 4 1 mult 25 gives 81 50 100 25
original 2 4 3 mult 33 gives 107 66 132 99
original 2 5 1 mult 17 gives 71 34 85 17
original 2 5 2 mult 37 gives 149 74 185 74
original 2 5 3 mult 1 gives 4 2 5 3
original 2 5 4 mult 49 gives 205 98 245 196
original 2 5 5 mult 29 gives 133 58 145 145
original 2 6 1 mult 45 gives 233 90 270 45
original 2 6 3 mult 53 gives 259 106 318 159
original 2 6 5 mult 23 gives 119 46 138 115
original 3 1 1 mult 5 gives 14 15 5 5
original 3 2 1 mult 23 gives 63 69 46 23
original 3 2 2 mult 13 gives 35 39 26 26
original 3 3 1 mult 14 gives 41 42 42 14
original 3 3 2 mult 31 gives 89 93 93 62
original 3 4 1 mult 5 gives 17 15 20 5
original 3 4 2 mult 19 gives 63 57 76 38
original 3 4 3 mult 43 gives 145 129 172 129
original 3 4 4 mult 25 gives 91 75 100 100
original 3 5 1 mult 11 gives 45 33 55 11
original 3 5 2 mult 47 gives 187 141 235 94
original 3 5 3 mult 26 gives 103 78 130 78
original 3 5 4 mult 59 gives 243 177 295 236
original 3 5 5 mult 17 gives 76 51 85 85
original 3 6 1 mult 55 gives 271 165 330 55
original 3 6 2 mult 29 gives 139 87 174 58
original 3 6 4 mult 35 gives 167 105 210 140
original 3 6 5 mult 1 gives 5 3 6 5
original 4 1 1 mult 17 gives 65 68 17 17
original 4 2 1 mult 37 gives 137 148 74 37
original 4 3 1 mult 7 gives 26 28 21 7
original 4 3 2 mult 45 gives 163 180 135 90
original 4 3 3 mult 25 gives 91 100 75 75
original 4 4 1 mult 49 gives 193 196 196 49
original 4 4 3 mult 19 gives 73 76 76 57
original 4 5 1 mult 29 gives 127 116 145 29
original 4 5 2 mult 61 gives 261 244 305 122
original 4 5 3 mult 33 gives 140 132 165 99
original 4 5 4 mult 73 gives 317 292 365 292
original 4 5 5 mult 41 gives 189 164 205 205
original 4 6 1 mult 1 gives 5 4 6 1
original 4 6 3 mult 11 gives 53 44 66 33
original 4 6 5 mult 93 gives 469 372 558 465
original 5 1 1 mult 13 gives 63 65 13 13
original 5 2 1 mult 55 gives 259 275 110 55
original 5 2 2 mult 29 gives 133 145 58 58
original 5 3 1 mult 30 gives 139 150 90 30
original 5 3 2 mult 21 gives 95 105 63 42
original 5 3 3 mult 17 gives 76 85 51 51
original 5 4 1 mult 67 gives 315 335 268 67
original 5 4 2 mult 5 gives 23 25 20 10
original 5 4 3 mult 75 gives 341 375 300 225
original 5 4 4 mult 41 gives 189 205 164 164
original 5 5 1 mult 19 gives 94 95 95 19
original 5 5 2 mult 79 gives 383 395 395 158
original 5 5 3 mult 14 gives 67 70 70 42
original 5 5 4 mult 91 gives 439 455 455 364
original 5 6 1 mult 87 gives 467 435 522 87
original 5 6 2 mult 15 gives 79 75 90 30
original 5 6 3 mult 95 gives 493 475 570 285
original 5 6 4 mult 51 gives 265 255 306 204
original 5 6 5 mult 37 gives 197 185 222 185
original 5 6 6 mult 61 gives 341 305 366 366
original 6 1 1 mult 37 gives 217 222 37 37
original 6 2 1 mult 11 gives 63 66 22 11
original 6 3 1 mult 41 gives 230 246 123 41
original 6 3 2 mult 85 gives 467 510 255 170
original 6 4 1 mult 89 gives 497 534 356 89
original 6 4 3 mult 97 gives 523 582 388 291
original 6 5 1 mult 49 gives 279 294 245 49
original 6 5 2 mult 101 gives 565 606 505 202
original 6 5 3 mult 53 gives 292 318 265 159
original 6 5 4 mult 113 gives 621 678 565 452
original 6 5 5 mult 61 gives 341 366 305 305
original 6 6 1 mult 109 gives 649 654 654 109
original 6 6 5 mult 133 gives 773 798 798 665
$endgroup$
add a comment |
$begingroup$
take any triple $b,c,d,$ with $gcd(b,c,d)=1,$ there is a smallest $k$ such that $(a,kb,kc,kd)$ is a solution with $a$ integral, while $gcd(a,kb,kc,kd) = 1.$ Also
$$ k = frac{2b^2+c^2+d^2}{gcd left( 2b^2+c^2+d^2 ;, ;2b^3+c^3+d^3 right)} $$
original 1 1 1 mult 1 gives 1 1 1 1
original 1 2 1 mult 7 gives 11 7 14 7
original 1 2 2 mult 5 gives 9 5 10 10
original 1 3 1 mult 2 gives 5 2 6 2
original 1 3 2 mult 15 gives 37 15 45 30
original 1 3 3 mult 5 gives 14 5 15 15
original 1 4 1 mult 19 gives 67 19 76 19
original 1 4 2 mult 11 gives 37 11 44 22
original 1 4 3 mult 9 gives 31 9 36 27
original 1 4 4 mult 17 gives 65 17 68 68
original 1 5 1 mult 7 gives 32 7 35 7
original 1 5 2 mult 31 gives 135 31 155 62
original 1 5 3 mult 18 gives 77 18 90 54
original 1 5 4 mult 43 gives 191 43 215 172
original 1 5 5 mult 13 gives 63 13 65 65
original 1 6 1 mult 13 gives 73 13 78 13
original 1 6 2 mult 21 gives 113 21 126 42
original 1 6 3 mult 47 gives 245 47 282 141
original 1 6 4 mult 9 gives 47 9 54 36
original 1 6 5 mult 9 gives 49 9 54 45
original 1 6 6 mult 37 gives 217 37 222 222
original 2 1 1 mult 5 gives 9 10 5 5
original 2 2 1 mult 13 gives 25 26 26 13
original 2 3 1 mult 9 gives 22 18 27 9
original 2 3 2 mult 7 gives 17 14 21 14
original 2 3 3 mult 13 gives 35 26 39 39
original 2 4 1 mult 25 gives 81 50 100 25
original 2 4 3 mult 33 gives 107 66 132 99
original 2 5 1 mult 17 gives 71 34 85 17
original 2 5 2 mult 37 gives 149 74 185 74
original 2 5 3 mult 1 gives 4 2 5 3
original 2 5 4 mult 49 gives 205 98 245 196
original 2 5 5 mult 29 gives 133 58 145 145
original 2 6 1 mult 45 gives 233 90 270 45
original 2 6 3 mult 53 gives 259 106 318 159
original 2 6 5 mult 23 gives 119 46 138 115
original 3 1 1 mult 5 gives 14 15 5 5
original 3 2 1 mult 23 gives 63 69 46 23
original 3 2 2 mult 13 gives 35 39 26 26
original 3 3 1 mult 14 gives 41 42 42 14
original 3 3 2 mult 31 gives 89 93 93 62
original 3 4 1 mult 5 gives 17 15 20 5
original 3 4 2 mult 19 gives 63 57 76 38
original 3 4 3 mult 43 gives 145 129 172 129
original 3 4 4 mult 25 gives 91 75 100 100
original 3 5 1 mult 11 gives 45 33 55 11
original 3 5 2 mult 47 gives 187 141 235 94
original 3 5 3 mult 26 gives 103 78 130 78
original 3 5 4 mult 59 gives 243 177 295 236
original 3 5 5 mult 17 gives 76 51 85 85
original 3 6 1 mult 55 gives 271 165 330 55
original 3 6 2 mult 29 gives 139 87 174 58
original 3 6 4 mult 35 gives 167 105 210 140
original 3 6 5 mult 1 gives 5 3 6 5
original 4 1 1 mult 17 gives 65 68 17 17
original 4 2 1 mult 37 gives 137 148 74 37
original 4 3 1 mult 7 gives 26 28 21 7
original 4 3 2 mult 45 gives 163 180 135 90
original 4 3 3 mult 25 gives 91 100 75 75
original 4 4 1 mult 49 gives 193 196 196 49
original 4 4 3 mult 19 gives 73 76 76 57
original 4 5 1 mult 29 gives 127 116 145 29
original 4 5 2 mult 61 gives 261 244 305 122
original 4 5 3 mult 33 gives 140 132 165 99
original 4 5 4 mult 73 gives 317 292 365 292
original 4 5 5 mult 41 gives 189 164 205 205
original 4 6 1 mult 1 gives 5 4 6 1
original 4 6 3 mult 11 gives 53 44 66 33
original 4 6 5 mult 93 gives 469 372 558 465
original 5 1 1 mult 13 gives 63 65 13 13
original 5 2 1 mult 55 gives 259 275 110 55
original 5 2 2 mult 29 gives 133 145 58 58
original 5 3 1 mult 30 gives 139 150 90 30
original 5 3 2 mult 21 gives 95 105 63 42
original 5 3 3 mult 17 gives 76 85 51 51
original 5 4 1 mult 67 gives 315 335 268 67
original 5 4 2 mult 5 gives 23 25 20 10
original 5 4 3 mult 75 gives 341 375 300 225
original 5 4 4 mult 41 gives 189 205 164 164
original 5 5 1 mult 19 gives 94 95 95 19
original 5 5 2 mult 79 gives 383 395 395 158
original 5 5 3 mult 14 gives 67 70 70 42
original 5 5 4 mult 91 gives 439 455 455 364
original 5 6 1 mult 87 gives 467 435 522 87
original 5 6 2 mult 15 gives 79 75 90 30
original 5 6 3 mult 95 gives 493 475 570 285
original 5 6 4 mult 51 gives 265 255 306 204
original 5 6 5 mult 37 gives 197 185 222 185
original 5 6 6 mult 61 gives 341 305 366 366
original 6 1 1 mult 37 gives 217 222 37 37
original 6 2 1 mult 11 gives 63 66 22 11
original 6 3 1 mult 41 gives 230 246 123 41
original 6 3 2 mult 85 gives 467 510 255 170
original 6 4 1 mult 89 gives 497 534 356 89
original 6 4 3 mult 97 gives 523 582 388 291
original 6 5 1 mult 49 gives 279 294 245 49
original 6 5 2 mult 101 gives 565 606 505 202
original 6 5 3 mult 53 gives 292 318 265 159
original 6 5 4 mult 113 gives 621 678 565 452
original 6 5 5 mult 61 gives 341 366 305 305
original 6 6 1 mult 109 gives 649 654 654 109
original 6 6 5 mult 133 gives 773 798 798 665
$endgroup$
take any triple $b,c,d,$ with $gcd(b,c,d)=1,$ there is a smallest $k$ such that $(a,kb,kc,kd)$ is a solution with $a$ integral, while $gcd(a,kb,kc,kd) = 1.$ Also
$$ k = frac{2b^2+c^2+d^2}{gcd left( 2b^2+c^2+d^2 ;, ;2b^3+c^3+d^3 right)} $$
original 1 1 1 mult 1 gives 1 1 1 1
original 1 2 1 mult 7 gives 11 7 14 7
original 1 2 2 mult 5 gives 9 5 10 10
original 1 3 1 mult 2 gives 5 2 6 2
original 1 3 2 mult 15 gives 37 15 45 30
original 1 3 3 mult 5 gives 14 5 15 15
original 1 4 1 mult 19 gives 67 19 76 19
original 1 4 2 mult 11 gives 37 11 44 22
original 1 4 3 mult 9 gives 31 9 36 27
original 1 4 4 mult 17 gives 65 17 68 68
original 1 5 1 mult 7 gives 32 7 35 7
original 1 5 2 mult 31 gives 135 31 155 62
original 1 5 3 mult 18 gives 77 18 90 54
original 1 5 4 mult 43 gives 191 43 215 172
original 1 5 5 mult 13 gives 63 13 65 65
original 1 6 1 mult 13 gives 73 13 78 13
original 1 6 2 mult 21 gives 113 21 126 42
original 1 6 3 mult 47 gives 245 47 282 141
original 1 6 4 mult 9 gives 47 9 54 36
original 1 6 5 mult 9 gives 49 9 54 45
original 1 6 6 mult 37 gives 217 37 222 222
original 2 1 1 mult 5 gives 9 10 5 5
original 2 2 1 mult 13 gives 25 26 26 13
original 2 3 1 mult 9 gives 22 18 27 9
original 2 3 2 mult 7 gives 17 14 21 14
original 2 3 3 mult 13 gives 35 26 39 39
original 2 4 1 mult 25 gives 81 50 100 25
original 2 4 3 mult 33 gives 107 66 132 99
original 2 5 1 mult 17 gives 71 34 85 17
original 2 5 2 mult 37 gives 149 74 185 74
original 2 5 3 mult 1 gives 4 2 5 3
original 2 5 4 mult 49 gives 205 98 245 196
original 2 5 5 mult 29 gives 133 58 145 145
original 2 6 1 mult 45 gives 233 90 270 45
original 2 6 3 mult 53 gives 259 106 318 159
original 2 6 5 mult 23 gives 119 46 138 115
original 3 1 1 mult 5 gives 14 15 5 5
original 3 2 1 mult 23 gives 63 69 46 23
original 3 2 2 mult 13 gives 35 39 26 26
original 3 3 1 mult 14 gives 41 42 42 14
original 3 3 2 mult 31 gives 89 93 93 62
original 3 4 1 mult 5 gives 17 15 20 5
original 3 4 2 mult 19 gives 63 57 76 38
original 3 4 3 mult 43 gives 145 129 172 129
original 3 4 4 mult 25 gives 91 75 100 100
original 3 5 1 mult 11 gives 45 33 55 11
original 3 5 2 mult 47 gives 187 141 235 94
original 3 5 3 mult 26 gives 103 78 130 78
original 3 5 4 mult 59 gives 243 177 295 236
original 3 5 5 mult 17 gives 76 51 85 85
original 3 6 1 mult 55 gives 271 165 330 55
original 3 6 2 mult 29 gives 139 87 174 58
original 3 6 4 mult 35 gives 167 105 210 140
original 3 6 5 mult 1 gives 5 3 6 5
original 4 1 1 mult 17 gives 65 68 17 17
original 4 2 1 mult 37 gives 137 148 74 37
original 4 3 1 mult 7 gives 26 28 21 7
original 4 3 2 mult 45 gives 163 180 135 90
original 4 3 3 mult 25 gives 91 100 75 75
original 4 4 1 mult 49 gives 193 196 196 49
original 4 4 3 mult 19 gives 73 76 76 57
original 4 5 1 mult 29 gives 127 116 145 29
original 4 5 2 mult 61 gives 261 244 305 122
original 4 5 3 mult 33 gives 140 132 165 99
original 4 5 4 mult 73 gives 317 292 365 292
original 4 5 5 mult 41 gives 189 164 205 205
original 4 6 1 mult 1 gives 5 4 6 1
original 4 6 3 mult 11 gives 53 44 66 33
original 4 6 5 mult 93 gives 469 372 558 465
original 5 1 1 mult 13 gives 63 65 13 13
original 5 2 1 mult 55 gives 259 275 110 55
original 5 2 2 mult 29 gives 133 145 58 58
original 5 3 1 mult 30 gives 139 150 90 30
original 5 3 2 mult 21 gives 95 105 63 42
original 5 3 3 mult 17 gives 76 85 51 51
original 5 4 1 mult 67 gives 315 335 268 67
original 5 4 2 mult 5 gives 23 25 20 10
original 5 4 3 mult 75 gives 341 375 300 225
original 5 4 4 mult 41 gives 189 205 164 164
original 5 5 1 mult 19 gives 94 95 95 19
original 5 5 2 mult 79 gives 383 395 395 158
original 5 5 3 mult 14 gives 67 70 70 42
original 5 5 4 mult 91 gives 439 455 455 364
original 5 6 1 mult 87 gives 467 435 522 87
original 5 6 2 mult 15 gives 79 75 90 30
original 5 6 3 mult 95 gives 493 475 570 285
original 5 6 4 mult 51 gives 265 255 306 204
original 5 6 5 mult 37 gives 197 185 222 185
original 5 6 6 mult 61 gives 341 305 366 366
original 6 1 1 mult 37 gives 217 222 37 37
original 6 2 1 mult 11 gives 63 66 22 11
original 6 3 1 mult 41 gives 230 246 123 41
original 6 3 2 mult 85 gives 467 510 255 170
original 6 4 1 mult 89 gives 497 534 356 89
original 6 4 3 mult 97 gives 523 582 388 291
original 6 5 1 mult 49 gives 279 294 245 49
original 6 5 2 mult 101 gives 565 606 505 202
original 6 5 3 mult 53 gives 292 318 265 159
original 6 5 4 mult 113 gives 621 678 565 452
original 6 5 5 mult 61 gives 341 366 305 305
original 6 6 1 mult 109 gives 649 654 654 109
original 6 6 5 mult 133 gives 773 798 798 665
edited Jan 5 at 20:01
answered Jan 5 at 19:40
Will JagyWill Jagy
103k5101200
103k5101200
add a comment |
add a comment |
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3063069%2fsolutions-to-a-2-a2-2-b2-c2-d2-2-a3-2-b3-c3-d3-in-in%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
$begingroup$
Would you append an update to this instead of duplication?
$endgroup$
– metamorphy
Jan 5 at 18:52
$begingroup$
@metamorphy it is not a duplication
$endgroup$
– user631773
Jan 5 at 18:53
$begingroup$
Very similar to ... math.stackexchange.com/questions/3062146/…
$endgroup$
– Donald Splutterwit
Jan 5 at 19:11