Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 3 X 3 plus 2,1 2,2 2,3 1,2 3,2.
A146001
Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 3 X 3 plus 2,1 2,2 2,3 1,2 3,2.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =1a(4) =4a(5) =3a(6) =13a(7) =10a(8) =51a(9) =49a(10) =310a(11) =338a(12) =2482a(13) =3185a(14) =28263a(15) =43203a(16) =449926a(17) =801916a(18) =9914815a(19) =21045123a(20) =308205077a(21) =768844389a(22) =13283687618a(23) =39245465846a(24) =803638667971
External references
- oeis: A146001