Number of n X n binary matrices, symmetric under 90-degree rotation, with no more than 2 ones in any 2 X 2 subblock.
A141507
Number of n X n binary matrices, symmetric under 90-degree rotation, with no more than 2 ones in any 2 X 2 subblock.
Terms
- a(0) =1a(1) =2a(2) =1a(3) =5a(4) =7a(5) =49a(6) =93a(7) =1237a(8) =4141a(9) =89949a(10) =498037a(11) =18459425a(12) =173151965a(13) =10776871089a(14) =170022693228
External references
- oeis: A141507