Prove tha number $19 \cdot 8^n +17$ is composite for every positive integer $n$
Problem
Source: Regional Olympiad - Federation of Bosnia and Herzegovina 2012
Tags: number theory, Composite
Source: Regional Olympiad - Federation of Bosnia and Herzegovina 2012
Tags: number theory, Composite
Prove tha number $19 \cdot 8^n +17$ is composite for every positive integer $n$