MathDB

1

Part of 2022 Moldova Team Selection Test

Problems(1)

n^{5n-1}+n^{5n-2}+n^{5n-3}+n+1

Source: Moldova TST 2022

4/1/2022
Show that for every integer n≥2n \geq 2 the number a=n5n−1+n5n−2+n5n−3+n+1a=n^{5n-1}+n^{5n-2}+n^{5n-3}+n+1 is a composite number.
number theory