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 1-4 of 4 results.

A196991 Number of fixed polycairos with n cells.

Original entry on oeis.org

4, 10, 32, 112, 412, 1572, 6148, 24494, 98992, 404650, 1669496, 6941226, 29047568, 122235518, 516860460, 2194691988, 9353657788
Offset: 1

Views

Author

Joseph Myers, Oct 08 2011

Keywords

Crossrefs

Extensions

a(16)-a(17) from Johann Peters, Aug 05 2024

A159866 Number of 2-sided n-polycairos.

Original entry on oeis.org

1, 2, 5, 17, 55, 206, 781, 3099, 12421, 50725, 208870, 868238, 3631673, 15281827, 64610493, 274346429, 1169219224, 4999544053, 21440702381, 92192889106
Offset: 1

Views

Author

Eric W. Weisstein, Apr 24 2009

Keywords

Comments

Consider the Laves tiling of the plane by equilateral pentagons with two 90-degree angles (and all edges equal), with symbol [3^2.4.3.4], as seen for example in Fig. 2.7.1 of Grünbaum and Shephard, p. 96. Sequence gives number of n-celled connected animals that can be drawn on this grid. If we replace this tiling by the square grid tiling [4^4], we get the classical polyomino problem (see A000105). - N. J. A. Sloane, Aug 17 2006

References

  • Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987.

Crossrefs

Extensions

a(11)-a(15) from Joseph Myers, Oct 03 2011
a(16)-a(20) from Bert Dobbelaere, Jun 02 2025

A151535 Number of 1-sided strip polycairos with n cells.

Original entry on oeis.org

1, 3, 7, 19, 47, 125, 310, 803, 2020, 5144, 12986, 32829, 82728, 208461, 524092, 1317284, 3305350, 8291010, 20770830
Offset: 1

Views

Author

Ed Pegg Jr, May 13 2009

Keywords

Crossrefs

Extensions

a(13)-a(19) from Joseph Myers, Oct 03 2011

A151536 Number of 2-sided strip polycairos with n cells.

Original entry on oeis.org

1, 2, 4, 10, 25, 64, 158, 405, 1018, 2580, 6512, 16435, 41411, 104280, 262161, 658763, 1652954, 4145802, 10386103
Offset: 1

Views

Author

Ed Pegg Jr, May 13 2009

Keywords

Crossrefs

Extensions

a(13)-a(19) from Joseph Myers, Oct 03 2011
Showing 1-4 of 4 results.