This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A350739 #17 Apr 26 2023 07:05:47 %S A350739 2,1,4,14,47,178,697,2746,11071,45093,185341,767786,3201291,13420045, %T A350739 56524684 %N A350739 Number of polykagomes with n cells, distinguishing mirror images. %C A350739 A polykagome is a set of adjacent cells on the trihexagonal grid. %H A350739 George Sicherman, <a href="https://sicherman.net/kgcat/">Catalogue of Polykagomes</a> %H A350739 Wikipedia, <a href="https://en.wikipedia.org/wiki/Trihexagonal_tiling">Trihexagonal tiling</a> %e A350739 On the trihexagonal grid, a triangle can be adjacent only to a hexagon and vice versa. The only shape with 2 cells is a triangle joined to a hexagon, so a(2) = 1. %Y A350739 Cf. A343398, which identifies mirror images. %K A350739 nonn,hard,more %O A350739 1,1 %A A350739 _George Sicherman_, Jan 12 2022 %E A350739 a(12)-a(15) from _John Mason_, Mar 04 2022