Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 3X3 tee 1,1 1,2 1,3 2,2 3,2 in any orientation.
A146008
Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 3X3 tee 1,1 1,2 1,3 2,2 3,2 in any orientation.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =10a(7) =5a(8) =94a(9) =17a(10) =755a(11) =53a(12) =7939a(13) =559a(14) =210819a(15) =10558a(16) =8799077a(17) =208889a(18) =469946628a(19) =6272332a(20) =39105876330a(21) =353563401a(23) =30617473617
External references
- oeis: A146008