MathDB

C3

Part of 2018-IMOC

Problems(1)

L-tiling axb chessboard, # of grid covered even times

Source: IMOC 2018 C3

8/16/2021
Given an a×ba\times b chessboard where a,b≥3a,b\ge3, alice wants to use only LL-dominoes (as the figure shows) to cover this chessboard. How many grids, at least, are covered even times? https://services.artofproblemsolving.com/download.php?id=YXR0YWNobWVudHMvNi82LzhmZDkwMGQzZjU3M2QxMzk4Y2NjNDg5ZTMwM2ZmYjJiMWU3MmUwLnBuZw==&rn=MjAxOC1DMy5wbmc=
combinatorics