SEAMO 2027 - Paper D - SET 02 - Self-study Question 19

How many positive integers $n\le2020$ satisfy $\left\lfloor n/2\right\rfloor+\left\lfloor n/3\right\rfloor+\left\lfloor n/6\right\rfloor=n$? Here $\lfloor x\rfloor$ is the greatest integer less than or equal to $x$.