A393735 Number of free polyominoes in the {7,5} tessellation of the hyperbolic plane.

1, 1, 3, 16, 112, 1009, 10026, 106744, 1181868, 13493188, 157721486, 1879935579

Offset

1,3

Links

Table of n, a(n) for n=1..12.

Formula

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=5 and P{p,oo} = A005419.

Crossrefs

Cf. A333018, A393734, A393736, A393737, A393738, A005419.

Sequence in context: A002404 A097142 A039751 * A393736 A393737 A393738

Adjacent sequences: A393732 A393733 A393734 * A393736 A393737 A393738

Keyword

nonn,more

Author

John Mason, Érika Roldán, and Rosemberg Toalá-Enríquez, Mar 01 2026

Status

approved