MathDB

Modular NT

Source: Romania JBMO TST 2024 Day 1 P1

July 31, 2024

number theorymodular arithmeticprime numbers

Problem Statement

Find all the positive integers

a{}

and

b{}

such that

(7^a-5^b)/8

is a prime number.
Cosmin Manea and Dragoș Petrică