User:Rpresser/fnord

$$ f_n(x) = \begin{cases} x - \frac{1}{n} \lfloor nx \rfloor & \mbox{if }\lfloor nx \rfloor \equiv 0 mod 2 \\ \frac{1}{n} \lfloor nx \rfloor - x & \mbox{if }\lfloor nx \rfloor \equiv 1 mod 2 \end{cases} $$