Usual integer division rounds down: a b = ⌊ a b ⌋ {\displaystyle {\frac {a}{b}}=\left\lfloor {\frac {a}{b}}\right\rfloor } for a , b ∈ N , b ≠ 0 {\displaystyle a,b\in \mathbb {N} ,b\neq 0} .