M(a, b) = a -1/b +b(b + 3/a) is integer => square also
Source: 2010 Dutch IMO TST2 p3
January 10, 2020
number theoryPerfect Square
Problem Statement
(a) Let and be positive integers such that is an integer.
Prove that is a square.
(b) Find nonzero integers and such that is a positive integer, but not a square.