lean_workbook_plus_18708

Prove that, for any ${ n \in \mathbb N}$ , \n $\left\lfloor{n \over 3}\right\rfloor+\left\lfloor{n+2 \over 6}\right\rfloor+\left\lfloor{n+4 \over 6}\right\rfloor=\left\lfloor{n \over 2}\right\rfloor+\left\lfloor{n+3 \over 6}\right\rfloor.$\n