Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1101-0111-0001 pattern in any orientation.
A147237
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1101-0111-0001 pattern in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =3a(7) =19a(8) =37a(9) =71a(10) =177a(11) =551a(12) =1807a(13) =6509a(14) =26627a(15) =139987a(16) =688205a(17) =4186827a(18) =24218141a(19) =169157335a(20) =1233973193
External references
- oeis: A147237