Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 3X3 el 1,1 1,2 1,3 2,3 3,3 in any orientation.
A146035
Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 3X3 el 1,1 1,2 1,3 2,3 3,3 in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =3a(7) =3a(8) =7a(9) =7a(10) =15a(11) =15a(12) =39a(13) =39a(14) =189a(15) =189a(16) =995a(17) =995a(18) =5569a(19) =5569a(20) =37913a(21) =37913a(22) =366061a(23) =366061a(24) =4244909a(25) =4244909a(26) =58320195a(27) =58320195a(28) =974389263a(29) =974389263
External references
- oeis: A146035