Number of polyiamonds with n cells that tile the plane isohedrally but not by translation or by 180-degree rotation (Conway criterion).

A075222

Number of polyiamonds with n cells that tile the plane isohedrally but not by translation or by 180-degree rotation (Conway criterion).

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =2a(7) =10a(8) =22a(9) =54a(10) =52a(11) =534a(12) =523a(13) =1339a(14) =3218a(15) =9315a(16) =2177a(17) =29426a(18) =15423a(19) =101314a(20) =140072a(21) =110794a(22) =46748a(23) =1639279a(24) =710736a(25) =970251a(26) =3002062a(27) =8462256a(28) =895291a(29) =29458807

External references