- #1

- 15

- 0

## Homework Statement

Prove that

[tex]

11^n - 4^n

[/tex]

is a multiple of 7

## Homework Equations

N/A

## The Attempt at a Solution

I substituted k+1 in for n and simplified to get

[tex]

11(11^k)-4(4^k)

[/tex]

but after this point I get stuck. Any help would be appreciated.