A395888 - OEIS

%I #5 May 17 2026 12:43:44

%S 1,1,3,26,203,1989,20254,219388,2459694,28430925,336472173,4061865648,

%T 49856682527,620728583489

%N Number of oriented polyominoes in the {7,8} 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">Index entries for sequences related to non-euclidean polyforms</a>

%F a(n) = P{p,q}(n) (the number of oriented {p,q} polyominoes of size n) is equal to P{p,oo}(n) for n <= q. In this case, P{p,oo} = A389561.

%t (* Cf. A394862 with p=7 and q=8. *)

%Y Cf. A389561, A393738, A394862.

%K nonn,more

%O 1,3

%A _John Mason_, Érika Roldán, and Rosemberg Toalá-Enríquez, May 16 2026