Highest degree for 3-layer power tower (IMO ShortList 1991)
Source: IMO ShortList 1991, Problem 18 (BUL 1)
August 15, 2008
algebrabinomial theoremnumber theoryDivisibilityIMO Shortlist
Problem Statement
Find the highest degree of for which divides the number 1990^{1991^{1992}} \plus{} 1992^{1991^{1990}}.