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Number of generalized polyforms on the trihexagonal tiling with n cells.
13

%I #32 Mar 04 2022 09:01:49

%S 1,2,1,4,9,30,97,373,1405,5630,22672,93045,384403,1602156,6712128,

%T 28268504

%N Number of generalized polyforms on the trihexagonal tiling with n cells.

%C This sequence counts "free" polyforms where holes are allowed. This means that two polyforms are considered the same if one is a rigid transformation (translation, rotation, reflection or glide reflection) of the other.

%H Peter Kagey, <a href="/A343398/a343398.hs.txt">Haskell program for computing sequence</a>.

%H Peter Kagey, <a href="/A343398/a343398.pdf">The a(4) = 9 generalized polyforms on the trihexagonal tiling with 4 cells</a>.

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Trihexagonal_tiling">Trihexagonal tiling</a>

%Y Same but distinguishing mirror images: A350739.

%Y Analogous for other tilings: A000105 (square), A000228 (hexagonal), A000577 (triangular), A197156 (prismatic pentagonal), A197159 (floret pentagonal), A197459 (rhombille), A197462 (kisrhombille), A197465 (tetrakis square), A309159 (snub square), A343406 (truncated hexagonal), A343577 (truncated square).

%K nonn,more,hard

%O 0,2

%A _Peter Kagey_, Apr 13 2021

%E a(12)-a(15) from _John Mason_, Mar 04 2022