Free chiral polyominoes with n squares, having 90-degree rotational symmetry about the center of a square of the underlying square matrix.
A351142
Free chiral polyominoes with n squares, having 90-degree rotational symmetry about the center of a square of the underlying square matrix.
Terms
- a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =0a(7) =0a(8) =0a(9) =0a(10) =0a(11) =1a(12) =2a(13) =0a(14) =0a(15) =3a(16) =7a(17) =0a(18) =0a(19) =14a(20) =25a(21) =0a(22) =0a(23) =55a(24) =90a(25) =0a(26) =0a(27) =216a(28) =319a(29) =0
External references
- oeis: A351142