Number of n X n symmetric binary matrices with each 1 adjacent to exactly 1 diagonally or antidiagonally neighboring 1.
A191273
Number of n X n symmetric binary matrices with each 1 adjacent to exactly 1 diagonally or antidiagonally neighboring 1.
Terms
- a(0) =1a(1) =4a(2) =9a(3) =25a(4) =168a(5) =1360a(6) =12423a(7) =197679a(8) =4404447a(9) =124898323a(10) =5318804048a(11) =324994451931
External references
- oeis: A191273