A393733 Number of free polyominoes in the {6,8} tessellation of the hyperbolic plane.

1, 1, 3, 12, 68, 483, 3946, 34485, 315795, 2984265, 28902705, 285520504, 2867712983

Offset

1,3

Links

Table of n, a(n) for n=1..13.

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=6, q=8 and P{p,oo} = A004127.

Crossrefs

Cf. A393729, A393730, A393731, A393732, A004127.

Sequence in context: A296979 A393731 A393732 * A004127 A058115 A101313

Adjacent sequences: A393730 A393731 A393732 * A393734 A393735 A393736

Keyword

nonn,more

Author

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

Status

approved