# Prime number determinatorer!

**Number Theory**Level pending

Suppose the mod function is defined as \(\text{mod}(x,y) = x- y \left\lfloor \dfrac{x}{y} \right\rfloor\). Then define \(\large f(x) = \text{mod}((x-(\text{mod}((x-1)!,x)),x)\) for all positive integers \(x\). Then \(f(x)\) is a function which returns 1 if \(x\) is prime, 0 if not.