notation: is not a factor of

Question

I know that a factor can denoted by |, for e.g:

if $x$ is divisible by $y$, then it can be notated by $x|y$.

However, I do not know how to denote when $x$ is not a factor of $y$.

What is the notation for is "not a factor of"?

Answer 1

The same symbol with a strike-through. I can think of a couple of ways.

$\texttt{\nmid}$ $$ \nmid $$

$\texttt{\not|}$ $$ \not| $$

Whatever suits you stylistically.