We say that a set S of integers is rootiful if, for any positive integer n and any a0,a1,⋯,an∈S, all integer roots of the polynomial a0+a1x+⋯+anxn are also in S. Find all rootiful sets of integers that contain all numbers of the form 2a−2b for positive integers a and b. number theoryIMO ShortlistIMO Shortlist 2019polynomial