Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1101-0111-0100 pattern in any orientation.

A146861

Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 1101-0111-0100 pattern in any orientation.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =5a(7) =19a(8) =37a(9) =77a(10) =131a(11) =515a(12) =1575a(13) =6459a(14) =26455a(15) =139873a(16) =647697a(17) =4036849a(18) =21133021a(19) =162531941a(20) =1088442077

External references