All Questions
4 questions with no upvoted or accepted answers
17
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808
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Decidability of $x^3+y^3+z^3 = c$
I wondering if it is known whether the following problem is algorithmically decidable or undecidable by Turing machines: given an integer c, determine if there are integers $(x,y,z)$ such that $x^3+y^...
9
votes
0
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346
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Is Videla's solution of Hilbert's tenth problem for rational functions over field of characteristic 2 wrong?
The paper in question.
Quick introduction to the problem: suppose that $F$ is a finite field of characteristic 2
(for purposes of this post $F = \mathbb{F}_2$ will suffice) and let $F[t]$ and $F(t)$ ...
7
votes
0
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274
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Is decidability reducible to unique decidability (perhaps in multilinear polynomial situations)?
Given a Diophantine equation it is not decidable if it has integer solution.
I. Is there a Diophantine set $\mathcal D_{unique}$ satisfying the properties
every member in $\mathcal D_{unique}$ is a ...
3
votes
0
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186
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Decidable equality for computable functions $\mathbb{N}\to\mathbb{N}$
Suppose we have two computable functions $f, g:\mathbb{N}\to\mathbb{N}$. When is $f=g$ algorithmically decidable?
For example it is decidable if $f$ and $g$ are polynomials of a priori known degree.