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%I #5 May 18 2026 10:55:08
%S 1,1,4,31,242,2391,24242,260266
%N Number of oriented polyominoes in the {9,3} tessellation of the hyperbolic plane.
%C For oriented polyominoes, chiral pairs are counted as two.
%H <a href="https://oeis.org/wiki/PF-Non-Euclidean">Wiki page indexing sequences related to non-euclidean polyforms</a>
%Y Cf. A393745.
%K nonn,more
%O 1,3
%A _John Mason_, Érika Roldán, and Rosemberg Toalá-Enríquez, May 18 2026