Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1000-1000-1111-1000 pattern in any orientation.
A147129
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1000-1000-1111-1000 pattern in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =7a(8) =25a(9) =45a(10) =79a(11) =171a(12) =569a(13) =1763a(14) =6023a(15) =22593a(16) =106741a(17) =481403a(18) =2734225a(19) =13695379a(20) =86954465
External references
- oeis: A147129