Luis H Gallardo's user avatar
Luis H Gallardo's user avatar
Luis H Gallardo's user avatar
Luis H Gallardo
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  • Member for 13 years, 4 months
12 votes
7 answers
4k views

Status of the Hadamard Circulant conjecture

9 votes
1 answer
1k views

All polynomials over a finite field are sums of $2$ square-free polynomials

8 votes
7 answers
1k views

Old question of Serre on discriminants of a sequence of polynomials

7 votes
2 answers
461 views

Perfect numbers $n$ such that $2^k(n+1)$ is also perfect

5 votes
3 answers
581 views

Positive integers $n$ that divide $\sigma_2(n)$

5 votes
4 answers
4k views

Eigenvectors of the Fourier matrix

4 votes
2 answers
493 views

Variant of Stephens result $\gcd(\Phi_p(q),\Phi_q(p))=2pq+1$ for $p=17$, $q=3313$

4 votes
1 answer
2k views

Irreducibility of some trinomials modulo $p$

3 votes
1 answer
701 views

About Duro Kurepa function: $ku(n)=0!+1!+ \cdots+(n-1)! \pmod{n}$

3 votes
5 answers
1k views

Even Perfect numbers $n$ with $n+1$ prime

3 votes
1 answer
333 views

Mersenne numbers represented by a Quadratic polynomial in two variables

3 votes
2 answers
519 views

Circulant $\lbrace -1,1 \rbrace $ matrices with eigenvalues seen in first row

3 votes
1 answer
308 views

Can two Consecutive Polynomials both be perfect ?

3 votes
1 answer
335 views

Arithmetic closed subsets

3 votes
0 answers
734 views

Equation $\sigma(2z-1)=3z$

3 votes
2 answers
547 views

Reducible trinomials $x^{odd}+x^2+s(t)$ in characteristic $2$

3 votes
1 answer
298 views

A kind of `pell` equation in characteristic $2.$

2 votes
1 answer
528 views

Characterizing degree $n$ polynomials that are $n$-th powers in $GF(p)[t]$

2 votes
1 answer
329 views

Symmetric polynomials preserving $-1,1$ matrices

2 votes
1 answer
580 views

Something new in old question about sums of three polynomial cubes ?

2 votes
1 answer
394 views

Solutions of a exponential diophantine equation involving the $\sigma$ function

2 votes
0 answers
268 views

Solutions of $\sigma(p^n)=\sigma(q^m)$

1 vote
0 answers
327 views

Signature of quadratic form associated to an integral circulant matrix with only real eigenvalues

1 vote
2 answers
518 views

Zeros of a sequence related to roots of unity

1 vote
1 answer
379 views

Asymptotic upper bounds for some convolution sums

1 vote
3 answers
334 views

obtaining all vectors of given length and with with $+-1$ entries from a given one

1 vote
0 answers
491 views

Dieudonné and generators of the orthogonal group

1 vote
0 answers
188 views

Binary `neighbors` perfect polynomials, instead of `consecutive`

1 vote
1 answer
794 views

If Ramanujan's tau function has a prime power zero then $\ldots$

1 vote
0 answers
348 views

J. T. B. Beard's algorithm to catch `perfect polynomials`