2005 Putnam B1: Find a Polynomial
Solution 1:
For any real number $r$, $\left\lfloor 2r\right\rfloor-2\left\lfloor r\right\rfloor$ can be only zero or one, hence $$ P(x,y) = (y-2x)(y-2x-1) $$ works.
2005 Putnam B1: Find a Polynomial
Solution 1:
For any real number $r$, $\left\lfloor 2r\right\rfloor-2\left\lfloor r\right\rfloor$ can be only zero or one, hence $$ P(x,y) = (y-2x)(y-2x-1) $$ works.