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%I #9 Mar 07 2026 04:37:05
%S 1,1,3,16,112,1020,10209,109673,1225914,14137194,166972947,2011515207
%N Number of free polyominoes in the {7,6} tessellation of the hyperbolic plane.
%F a(n) = P{p,q}(n) (the number of {p,q} polyominoes of size n) is equal to P{p,oo}(n) for n <= q; also P{p,q}(q+1) = P{p,oo}(q+1) + floor((p-1)/2) - floor((3+q(p-2))/2). In this case, p=7, q=6 and P{p,oo} = A005419.
%Y Cf. A333018, A393734, A393735, A393737, A393738, A005419.
%K nonn,more
%O 1,3
%A _John Mason_, Érika Roldán, and Rosemberg Toalá-Enríquez, Mar 01 2026