1720164275

Appears in sequences

• Number of n X n binary arrays symmetric about main diagonal with all 1's connected only in a 2 X 2 block with tail 1,1 1,2 1,3 2,2 2,3 in any orientation.at n=12A146049
• Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 2X2 block with tail 1,1 1,2 1,3 2,2 2,3 in any orientation.at n=26A146051
• Number of n X n binary arrays symmetric about the diagonal and under 90 degree rotation with all ones connected only in a 2X2 block with tail 1,1 1,2 1,3 2,2 2,3 in any orientation.at n=27A146051