Questions tagged [computational-number-theory]
This tag is for questions regarding to computational number theory, the branch of number theory concerned with finding and implementing efficient computer algorithms for solving various problems in number theory.
59 questions
2 votes
0 answers
117 views
When a cubic irrational can be written in terms of two nonnegative powers?
Choose rational numbers $p$, $q$, $r$, and choose a zero $\alpha$ of the cubic polynomial $\alpha^3+p\cdot\alpha^2+q\cdot\alpha+r$. What is an efficient algorithm for deciding, given nonzero rational ...
0 votes
0 answers
245 views
Efficient algorithm for solving Diophantine equation $x ^ 2+y ^ 3+z ^ 5=w ^ 7$ with $\gcd (x, y, z)=1$.
My Mathematica Codes: ...
1 vote
0 answers
150 views
If resultant $T(y) = \mathrm{Res}_{x}(f(x), y - g(x))$ have a nontrivial factors then can $f(x)$ also have a nontrivial factors?
This is a follow-up question to this question. In that question, we learned that if, $T(y) = \mathrm{Res}_{x}(f(x), y - g(x))$ , then $T(g(z))$ is divisible by $f(z)$. Now, my question is: If $T(y) = ...
1 vote
1 answer
94 views
Statistical patterns in primes generated from twin prime offsets
I analyzed primes generated by applying four linear offsets to the first element of twin prime pairs ( π , π + 2 ), for π β€ 1,000,000: π1 = 2π + 1, π2 = 2π + 7, π3 = 2π β 3, π4 = 2π + 3. ...
1 vote
0 answers
57 views
A question regarding Zassenhaus's Round 2 algorithm
I am currently reading Henri Cohen's excellent book, A Course in Computational Number Theory (1993). I have a small question regarding Zassenhaus's round 2 algorithm in this book, namely Algorithm 6.1....
2 votes
1 answer
207 views
Prime-detecting equation from PNAS 2024 fails computational verification
I'm attempting to verify the main computational claim from "Integer partitions detect the primes" by Craig, van Ittersum, and Ono (PNAS 2024, doi: 10.1073/pnas.2409417121). Their Theorem 1.1(...
6 votes
2 answers
487 views
Ideas and methods to compute absolute discriminant of fields.
Just for curiosity and fun, I was trying to calculate the discriminant of some unusual fields! Let $p=-3\cdot 11\cdot 29\cdot 31 = -29667$ and $q=2\cdot 5\cdot 11\cdot 19\cdot 29\cdot 31 = 1878910$. ...
2 votes
1 answer
88 views
Modular square root of a gaussian integer [duplicate]
Let $a$ and $x$ be Gaussian integers. How can I calculate the value of $x$ so that $x^2 \equiv a \pmod p$ where $p$ is a regular integer prime and $p \equiv 3 \pmod 4$ ? Example: $a = 2 + 5i$ $p = 7$ ...
3 votes
1 answer
212 views
Rank of Curve25519 lifted to $\mathbb{Q}$
Curve25519 has the well-known equation $E: y^2 = x^3 + 486662x^2 + x$ which is normally considered over the finite field $\mathbb{F}_p$, for $p = 2^{255}-19$. We can lift $E/\mathbb{F}_p$ to $E/\...
0 votes
1 answer
132 views
Computing primes of the form $x^2+ny^2$ [closed]
The book Primes of the form $x^2+ny^2$ by Cox discusses in detail the problem of when a prime $p$ can be written as $x^2+ny^2$, and along the way introduces more and more sophisticated number theory ...
1 vote
1 answer
90 views
A specific pattern occurs on numbers whose factors are coupled emirp.
Yesterday I asked Google if 403 is prime. The result showed that it has factors 13 and 31. So I wondered and wrote a little code that finds prime numbers which is also a prime when their digits are ...
1 vote
0 answers
96 views
Finding the root of the polynomial $T(y) = \mathrm{Res}_{x}(f(x), y \cdot h(x) - g(x))$.
This is a follow-up question to this question. In that question, we learned that if $T(y) = \mathrm{Res}_{x}(f(x), y - g(x))$ , then $T(g(z))$ is divisible by $f(z)$. More specifically, we can say ...
1 vote
1 answer
65 views
How can I check whether two sets of integer vectors generate the same subgroup?
How can I check whether two finite sets of $n$ independent vectors in $\Bbb Z^n$ generate the same additive subgroup of $\Bbb Z^n$? For example, $\{(2,7),(5,3)\}$ and $\{(-3,4),(5,3)\}$ have the same ...
1 vote
1 answer
83 views
Is it possible to define a function of several matrix variables whose inputs are variables in Sage?
I have a very little knowledge about Sage and this may be a dumb question, but I could not find anything about this. Is there any way to define a sage function of several variables whose arguments are ...
2 votes
0 answers
375 views
Linear forms in $1,\zeta(5)$ and $\zeta(7)$
I am reading an article "Well-poised hypergeometric service for diophantine problems of zeta values" by W. Zudilin. Consider the quantities defined here in pg. $617$ $$\tilde{F_n}:= \frac{1}{...