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%I #5 Mar 01 2026 09:38:52
%S 1,1,4,19,136,1226,12259,130435,1441755,16390245
%N Number of free polyominoes in the {9,3} tessellation of the hyperbolic plane.
%Y Cf. A259354.
%K nonn,more
%O 1,3
%A _John Mason_, Érika Roldán, and Rosemberg Toalá-Enríquez, Feb 27 2026