# Math Help - Making an equation for induction

1. ## Making an equation for induction

4^(n+1) + 5^(2n−1) is always divisible by 21

How can I make an equation that can be verified this by induction

2. Originally Posted by DeRSeD
4^(n+1) + 5^(2n−1) is always divisible by 21

How can I make an equation that can be verified this by induction
$4^{n+1}+ 5^{2n-1}= 21k$ for some k.