Questions tagged [diophantine-equations]

Questions on the use of Mathematica to find integer/rational solutions to equations.

92 questions
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How can I select four points on a sphere to make a regular tetrahedron so that its coordinates are integer numbers?

I want to select four points lie on the sphere (x-1)^2 + (y-3)^2 + (z-5)^2 = (5* Sqrt[3])^2 so that its coordinates are integer numbers to make a regular tetrahedron. I tried ClearAll[a, b, r, c]; a = 1; b = 3; c = 5; r = 5* Sqrt[3]; ss = …
Laurenso
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How can I get all squares on this sphere so that its coordinates are integer numbers?

I have the sphere (x-2)^2 + (y-4)^2 + (z-6)^2 = 15^2. I want to select all squares on this sphere so that its coordiantes are twelve different integer numbers like this {-8, 15, 8}, {-3, 6, 20}, {12, 9, 16}, {7, 18, 4}. I tried ClearAll[a, b, r,…
Laurenso
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Find out whether solutions exist rather than full-blown solution search

I have some quadratics, and I am trying to find out whether there exist solutions in the integers. The following tells me that the first does, wheraeas the second doesn't: Solve[2 + 4 x + 6 x^2 == 4 - 7 y + 3 y^2 && x < 0 && y < 0, x,…
martin
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How can I find four points on a circle to make a square so that its coordinates are integer numbers?

I have a circle and I want to select four points to make a square so that its coordiantes are eight different integer numbers like this {{7, 24}, {-24, 7}, {-7, -24}, {24, -7}} I tried ClearAll[a, b, r, c]; a = 0; b = 0; r = 25; ss = Subsets[{x, y}…
Laurenso
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Diophantine equation: getting a list of solutions for each coeficient

I'm trying to solve the following diophantine equation,$$x^3+dy^3=1$$ such that $$x,y \in \mathbb{Z} \land y \neq 0$$ and I want to form a list of solutions for each $$d\in[1,1000]; d\in\mathbb{N}$$ I wrote lista = Function[{d, i}, …
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Diophantine inequality that's not solved

Mathematica has trouble solving this Diophantine inequality: (* givens *) e = 653315732497285855855422606783 f = 1697172185816328002847853765504 g = 1650189636468405601822430434691 h = 2622176396697944576102111774652 m = 10^10 FindInstance[Abs[a f…
fgrieu
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How can I find all integer numbers so that mydistance is an integer number?

I am tring to selec two points A, B on the sphere (x-2)^2 + (y-4)^2 + (z-6)^2 ==9^2 so that EuclideanDistance[pA,pB] is an integer and coordinates of two point A, B are integer numbers. I know that, with distance AB= 12, I tried ClearAll[a, b, r,…
John Paul Peter
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Solving a quadratic equations over integers efficiently

I want to solve a quadratic equation over the integers but the naive method is unbearably slow (considering how easy the problem is). I have a positive non-degenerate quadratic form $Q$ on $\mathbb Z^n$(This is why I only have finitely many…