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%I #17 Apr 26 2023 07:05:47
%S 2,1,4,14,47,178,697,2746,11071,45093,185341,767786,3201291,13420045,
%T 56524684
%N Number of polykagomes with n cells, distinguishing mirror images.
%C A polykagome is a set of adjacent cells on the trihexagonal grid.
%H George Sicherman, <a href="https://sicherman.net/kgcat/">Catalogue of Polykagomes</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Trihexagonal_tiling">Trihexagonal tiling</a>
%e 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 Cf. A343398, which identifies mirror images.
%K nonn,hard,more
%O 1,1
%A _George Sicherman_, Jan 12 2022
%E a(12)-a(15) from _John Mason_, Mar 04 2022