A089456 Number of n-celled polyominoes with exactly 4 holes.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 179, 2509, 25609, 214932, 1578984, 10536260, 65411645, 383981499, 2156114468, 11678888362, 61413242603

Offset

1,17

Links

Table of n, a(n) for n=1..28.

Tomás Oliveira e Silva, Animal enumerations on the {4,4} Euclidean tiling

Crossrefs

Cf. A001419, A057418, A089454, A089455, A089457, A089458.

Sequence in context: A001596 A221115 A159326 * A298995 A299742 A299662

Adjacent sequences: A089453 A089454 A089455 * A089457 A089458 A089459

Keyword

hard,more,nonn

Author

Joseph Myers, Nov 04 2003

Extensions

a(27)-a(28) from Tomás Oliveira e Silva's page added by Andrei Zabolotskii, Sep 15 2025

Status

approved