Lifting The Exponent (LTE) Let $v_p(n)$ be the largest power of a prime $p$ that divides a positive integer $n$, and $x$, $y$ be any two integers such that $p \not\mid x$ and $p \not\mid y$, then
- When $p$ is odd
- If $p\mid x-y$, then $v_p(x^n-y^n) = v_p(x-y)+v_p(n)$
- If $n$ is odd and $p\mid x+y$, then $v_p(x^n+y^n) = v_p(x+y)+vp(n)$
- If $n$ is even and $p\mid x+y$, then $v_p(x^n+y^n) = 0$
- When $p=$
- If $2\mid x-y$ and $n$ is even, then $v_2(x^n-y^n)=v_2(x-y)+v_2(x+y)+v_2(n)-1$
- If $2\mid x-y$ and $n$ is odd, then $v_2(x^n-y^n)=v_2(x-y)$
- For all $p$
- if $gcd(n,p)=1$, and $p\mid x-y$, then $v_p(x^n-y^n)=v_p(x-y)$
- If $bcd(n,p)=1$, $p\mid x+y$ and n odd, then $v_p(x^n+y^n) = v_p(x+y)$