Number of (n+1)X(n+1) symmetric binary matrices without the pattern 1 1 diagonally or antidiagonally.
A190341
Number of (n+1)X(n+1) symmetric binary matrices without the pattern 1 1 diagonally or antidiagonally.
Terms
- a(0) =3a(1) =9a(2) =40a(3) =273a(4) =2727a(5) =41520a(6) =944307a(7) =32403123a(8) =1667310336a(9) =129124175985
External references
- oeis: A190341