New post in Elementary-number-theory

$a/b\bmod{m}$ when $m$ is not a prime

June 7th, 2022

$3^{15} \mod 17$ I would like using Fermat theorem and doing something like this $\frac{3^{16}}{3} \mod 17$ that is possible?

June 8th, 2022

Find all positive integers $n$ such that $n^4 − 1$ is divisible by 5.

June 8th, 2022

When a prime number p divides $ab$ then we have either p divides a or p divides b.Prove that $\sqrt {p} $ is not rational for any prime number p.

June 8th, 2022

Is this the general solution of finding the two original squares that add up to a given integer N?

June 8th, 2022

Show that: $97\mid (2^{48})-1$

June 8th, 2022

Greatest Common Divisor of prime numbers

June 8th, 2022

Prove that $n^2 + 1$ is not a multiple of $6$ for any positive integer $n$

June 8th, 2022

$x^4 = -1$ (mod $p$) implies p = 1 mod 8

December 17th, 2020

Find the pairs $(x,y) ; 0 \le x,y \le 18$ such that $19 \vert 3x+4y+5$

June 8th, 2022

Finding last two non-zero digits of 2016!

June 8th, 2022

If $\gcd(a,b) = 1$, show that $\gcd(2a+b, a+2b)=1 \mbox{ or } 3$

June 8th, 2022

Solve the following congruence: 2x ≡ 7 (mod 17)

June 8th, 2022

Number theory question from today's Pre - RMO

June 8th, 2022

Proof by induction with a prime number

June 8th, 2022

Are all numbers rational?

June 8th, 2022

How can I solve $4x + 51y = 9$ using congruences?

June 6th, 2022

how to prove that $n(n+1)$ can't be square?

June 8th, 2022

How to solve $ x^2+4x+2 \equiv 0 \pmod{49}$

June 8th, 2022

Suppose a, b and n are positive integers. Prove that (a^n) | (b^n) if and only if a | b.

November 19th, 2020

Extension of Fermat's little theorem with Carmichael numbers

June 8th, 2022

difference between 2 prime numbers

June 8th, 2022

Formula For Finding the Next Near Consecutive Perfect Square

August 7th, 2020

A number relatively prime to n in the integers mod n produces all the elements

June 8th, 2022

Show that $51| 10^{32n+9} - 7$

November 11th, 2020

The product of any two even integers is a multiple of 4

June 8th, 2022

How many coprime ordered pairs are there up to $N$?

June 8th, 2022

Let m and n be positive integers with (m,n) = 1. Prove that each divisor d > 0 of m*n can be written uniquely

June 8th, 2022

Show that the square of any odd positive integer is of the type 6q or 6q+ 3 or 6q + 5 where q is some integer

June 4th, 2020

If integers $a$ and $b$ are not both zero, then $\gcd(a,b)=\gcd(a-b,b)$

March 5th, 2020