a(n) is the number of concave n-celled polyominoes in the {4,5} tessellation of the hyperbolic plane.

A390199

a(n) is the number of concave n-celled polyominoes in the {4,5} tessellation of the hyperbolic plane.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =1a(7) =7a(8) =63a(9) =458a(10) =3209a(11) =21160a(12) =135308a(13) =843204a(14) =5165292

External references