New posts in Elementary Number Theory

Using Diophantine equation

Prove that the prime $p$ can only be $13$

Values of $a$ such that $x^5-x-a$ has quadratic factor

Computing Ramanujan asymptotic formula from Rademacher's formula for the partition function

If $2^{2k}-x^2\bigm|2^{2k}-1$ then $x=1$

What is the remainder when $1^n + 2^n + 3^n + \ldots + 99^n$ is divided by $1 + 2 + 3 + \ldots + 99$?

Last digit in $\sum_{k=1}^{999}k^m$ (olympiad question)

Sieve of Eratosthenes : why can we stop at the $\sqrt n$?

On finding triplets that satisfy a certain GCD and LCM property.

How can we prove that there are no other integers with $\phi(n)=2$ besides 3,4,6?