Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 5-point zee 1,1 2,1 2,2 2,3 3,3 in any orientation.
A146069
Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 5-point zee 1,1 2,1 2,2 2,3 3,3 in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =9a(7) =21a(8) =35a(9) =101a(10) =287a(11) =859a(12) =3329a(13) =15189a(14) =75035a(15) =399377a(16) =2204921a(17) =14787995a(18) =102936591a(19) =860535039a(20) =7743744003a(21) =81593423043a(22) =911784626279
External references
- oeis: A146069