Number of n X n binary arrays symmetric under 90-degree rotation with all ones connected only in a 1 X 5 or 5 X 1 block.
A145970
Number of n X n binary arrays symmetric under 90-degree rotation with all ones connected only in a 1 X 5 or 5 X 1 block.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =4a(7) =7a(8) =15a(9) =33a(10) =90a(11) =201a(12) =647a(13) =1861a(14) =7123a(15) =23236a(16) =101280a(17) =390759a(18) =2050696a(19) =9515925a(20) =59455120a(21) =328131409a(22) =2431442671a(23) =15797747304a(24) =137926288897
External references
- oeis: A145970