cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-3 of 3 results.

A056785 Number of polydominoes.

Original entry on oeis.org

1, 4, 23, 211, 2227, 25824, 310242, 3818983, 47752136, 604425323
Offset: 1

Views

Author

James Sellers, Aug 28 2000

Keywords

Comments

From Vicher's table.
This gives the number of polyominoes of order 2n that can be tiled by dominoes in at least one way. - Joseph Myers, Jun 10 2012

Links

Crossrefs

Cf. A056786, A213376, A213377, A213378.

Formula

a(n) + A213376(n) = A210996(n). - R. J. Mathar, Jan 30 2023

Extensions

Edited by T. D. Noe, Apr 09 2009
Offset corrected and a(6)-a(9) added by Joseph Myers, Jun 10 2012
a(10) added by Arthur O'Dwyer, Aug 28 2025

A213376 Number of polyominoes of order 2n that cannot be tiled by dominoes.

Original entry on oeis.org

0, 1, 12, 158, 2428, 37776, 591729, 9260272, 144869916
Offset: 1

Views

Author

Joseph Myers, Jun 10 2012

Keywords

Crossrefs

Cf. A056785, A056786, A213377, A213378.

Formula

a(n) + A056785(n) = A210996(n). - R. J. Mathar, Jan 30 2023

A213378 Number of polyominoes of order 2n that can be tiled by dominoes in more than one way.

Original entry on oeis.org

0, 1, 3, 41, 499, 6946, 95964, 1330807, 18395673
Offset: 1

Views

Author

Joseph Myers, Jun 10 2012

Keywords

Comments

Tilings related by a symmetry of the polyomino that is not a symmetry of the tiling count as distinct (thus, the square tetromino counts as being tiled in two distinct ways).

Crossrefs

Cf. A056785, A056786, A213376, A213377.
Showing 1-3 of 3 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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