All Questions

Given an $m\times n$ chess board, we place $p$ $2\times 1$ dominoes on the board so that they don't overlap. How many ways can we place them? When each square of the board is covered by a domino this ...

Given a positive integer $k\ge2$, let be $f_k(m,n)$ the number of ways to cover an $m × n$ rectangle with $mn/k$ tiles ( $1×k$ or $k×1$) $f_2(m,n)$ is kasteleyn formula $f_k(m,n)$?

Is there a non-enumerative proof that, in average, less than 50% of tiles in domino tiling of 2-by-n rectangle are vertical? It is a nice exercise with rational generating functions (or equivalently, ...