Problem
ALG-B1-M12-P021 Variant 6, Problem 1
#21
★★★★☆ Level 4 of 5
Find all integers \(n\) for which \(n^2+3n+5\) is divisible by \(n+1\).
Use \(n\equiv-1\pmod{n+1}\).
The remainder is \(1-3+5=3\). Need \(n+1\mid3\). Answer: \(n=0,-2,2,-4\).
Mock olympiad problem. Tags: divisibility.