MathDB
JBMO Shortlist 2020 N2

Source: JBMO Shortlist 2020

July 4, 2021
JuniorBalkanshortlist2020number theoryprime numbers

Problem Statement

Find all positive integers aa, bb, cc, and pp, where pp is a prime number, such that
73p2+6=9a2+17b2+17c273p^2 + 6 = 9a^2 + 17b^2 + 17c^2.