Number of legal tic-tac-toe (or noughts and crosses) positions after n plays, up to rotation and reflection.
A008907
Number of legal tic-tac-toe (or noughts and crosses) positions after n plays, up to rotation and reflection.
Terms
- a(0) =1a(1) =3a(2) =12a(3) =38a(4) =108a(5) =174a(6) =204a(7) =153a(8) =57a(9) =15
External references
- oeis: A008907