Number of n X n binary arrays symmetric about the diagonal and 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.
A146068
Number of n X n binary arrays symmetric about the diagonal and 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) =1a(7) =1a(8) =1a(9) =1a(10) =3a(11) =3a(12) =9a(13) =9a(14) =19a(15) =19a(16) =69a(17) =69a(18) =389a(19) =389a(20) =2287a(21) =2287a(22) =15081a(23) =15081a(24) =141721a(25) =141721a(26) =1694175a(27) =1694175a(28) =23795099a(29) =23795099
External references
- oeis: A146068