New posts in Congruences

Is there a nonzero solution to this infinite system of congruences?

Prove that $\sum_{n = 1}^{p - 1} n^{p - 1} \equiv (p - 1)! + p \pmod {p^2}$ with $p$ being an odd prime

For which values of $k$ is it known that there are infinitely many $n$, such that $2^{n+k}\equiv 1\pmod{n}$?

Ramanujan's tau function, $691$ congruence, and $\eta(z)^{12}$

What did Yu Jianchun discover about Carmichael numbers?

A congruence involving binomial coefficients

Congruence equation for Apery numbers