79925

Appears in sequences

• Number of polyiamonds with n cells that tile the plane by 180-degree rotation (Conway criterion) but not by translation.at n=18A075219
• Number of polyiamonds with n cells that tile the plane by 180-degree rotation (Conway criterion).at n=18A075220
• Number of polyiamonds with n cells that tile the plane by translation or by 180-degree rotation (Conway criterion).at n=18A075221
• Square array A(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where column k is the expansion of e.g.f. B(x)^k, where B(x) is the e.g.f. of A384809.at n=60A384811