A366334 Number of free (4,2)-polyominoids with n cells.

1, 2, 12, 95, 1267, 22349

Offset

1,2

Comments

A (D,d)-polyominoid is a connected set of d-dimensional unit cubes with integer coordinates in D-dimensional space, where two cubes are connected if they share a (d-1)-dimensional facet. For example, (3,2)-polyominoids are normal polyominoids (A075679), (D,D)-polyominoids are D-dimensional polyominoes (A000105, A038119, A068870, ...), and (D,1)-polyominoids are polysticks in D dimensions (A019988, A365559, A365561, ...).

Links

Table of n, a(n) for n=1..6.

Wikipedia, Polyominoid.

Index entries for sequences related to polyominoes.

Crossrefs

46th row of A366766.

Cf. A366335 (fixed).

Free (D,d)-polyominoids:

D\d| 1 2 3 4

---+--------------------------------

1 | A000012

2 | A019988 A000105

3 | A365559 A075679 A038119

4 | A365561 A366334 A366336 A068870

Sequence in context: A372202 A359692 A321057 * A247075 A239837 A239838

Adjacent sequences: A366331 A366332 A366333 * A366335 A366336 A366337

Keyword

nonn,hard,more

Author

Pontus von Brömssen, Oct 07 2023

Status

approved