MathDB

2

Part of 2022 SAFEST Olympiad

Problems(1)

Integers and divisibility

Source: 2022 Switzerland IMO TST, Problem 6

8/7/2022
Let n≥2n \geq 2 be an integer. Prove that if n2+4n+7nn\frac{n^2+4^n+7^n}{n} is an integer, then it is divisible by 11.
Integersnumber theoryDivisibility