What is the maximum number of queens you can place on a chessboard such that none of them can attack each other in one move?
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
By Pigeonhole Principle, if there are 5 queens on the board, then there must exist 2 queens on the same row or column, thereby attacking each other. Therefore, there are at most 4 queens on the board, which is satisfied by