Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1100-1000-1111 pattern in any orientation.
A146688
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1100-1000-1111 pattern in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =15a(8) =35a(9) =63a(10) =133a(11) =361a(12) =1225a(13) =3603a(14) =14173a(15) =68577a(16) =327107a(17) =1804859a(18) =9535581a(19) =56798795a(20) =377223653
External references
- oeis: A146688