MathDB
7^a - 3^b divides a^4 + b^2 (from IMO Shortlist 2007)

Source: ISL 2007, N1, VAIMO 2008, P4

April 21, 2008
DivisibilityIMO Shortlistnumber theory

Problem Statement

Find all pairs of natural numbers (a,b) (a, b) such that 7^a \minus{} 3^b divides a^4 \plus{} b^2.
Author: Stephan Wagner, Austria