This follows on from problem 44850 - X O X O
On a noughts and crosses board, how many possible unique combinations are there given a square grid of length n?
- All squares are populated.
- Number of naughts and number of crosses can only differ by a maximum of 1 I.E. The game was played until the board was full.
- A solution with more than one "win" cannot be valid as the game would have finished before the board was full!