# Identity in number theory

$$\displaystyle p^n-1$$ is a multiple of 2 where $$\displaystyle p$$ is a prime no and $$\displaystyle p\geq 3$$ and $$\displaystyle n$$ is a positive integer.

#### greg1313

That's unremarkable. $$\displaystyle \ p^n - 1 \$$ is a (negative, zero, or positive) multiple
of 2, depending, where p is any negative or positive odd integer, and n is an
integer greater than or equal to zero.

The main point is that there is nothing special about p being a prime (odd).

Last edited:
topsquark