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 1-7 of 7 results.

A103465 Number of polyominoes that can be formed from n regular unit pentagons (or polypents of order n).

Original entry on oeis.org

1, 1, 2, 7, 25, 118, 551, 2812, 14445, 76092, 403976, 2167116, 11698961, 63544050, 346821209, 1901232614
Offset: 1

Views

Author

Sascha Kurz, Feb 07 2005; definition revised and sequence extended Apr 12 2006 and again Jun 09 2006

Keywords

Comments

Number of 5-polyominoes with n pentagons. A k-polyomino is a non-overlapping union of n regular unit k-gons.
Unlike A051738, these are not anchored polypents but simple polypents. - George Sicherman, Mar 06 2006
Polypents (or 5-polyominoes in Koch and Kurz's terminology) can have holes and this enumeration includes polypents with holes. - George Sicherman, Dec 06 2007

Examples

			a(3)=2 because there are 2 geometrically distinct ways to join 3 regular pentagons edge to edge.

Links

Crossrefs

Cf. A103465, A103466, A103467, A103468, A103469, A103470, A103471, A103472, A103473, A120102, A120103, A120104.
Cf. A000105, A000577, A000228.

Extensions

Entry revised by N. J. A. Sloane, Jun 18 2006

A103473 Number of polyominoes consisting of 7 regular unit n-gons.

Original entry on oeis.org

24, 108, 551, 333, 558, 1605, 4418, 8350, 17507, 13512, 17775, 30467, 55264, 83252, 134422, 112514, 135175, 195122, 294091, 397852, 566007, 495773, 568602, 751172, 1031920, 1307384, 1729686, 1557663, 1737915, 2169846, 2808616, 3413064
Offset: 3

Views

Author

Sascha Kurz, Feb 07 2005

Keywords

Examples

			a(3)=24 because there are 24 polyiamonds consisting of 7 triangles and a(4)=108 because there are 108 polyominoes consisting of 7 squares.

Links

Crossrefs

Cf. A103469, A103470, A103471, A103472.
Cf. A000577, A000104, A000228, A103465, A103466, A103467, A103468, A103469, A103470, A103471, A103472, A115071, A120102, A120103, A120104.

Extensions

More terms from Sascha Kurz, Jun 09 2006

A120102 Number of polyominoes consisting of 8 regular unit n-gons.

Original entry on oeis.org

66, 369, 2812, 1448, 2876, 10102, 34838, 73675, 181127, 131801, 185297, 352375, 725869, 1180526, 2104485, 1694978, 2123088, 3291481, 5402087, 7739008, 11832175, 10079003, 11917261, 16624712, 24389611, 32317393, 45260884
Offset: 3

Views

Author

Sascha Kurz, Jun 09 2006

Keywords

Examples

			a(3)=66 because there are 66 polyiamonds consisting of 8 triangles and a(4)=369 because there are 369 polyominoes consisting of 8 squares.

Links

Crossrefs

Cf. A000577, A000104, A000228, A103465, A103466, A103467, A103468, A103469, A103470, A103471, A103472, A103473, A103465, A120103, A120104.

A120104 Number of polyominoes consisting of 10 regular unit n-gons.

Original entry on oeis.org

448, 4655, 76092, 30490, 80075, 430302, 2285047, 6078768, 20376032, 13303523, 21208739, 49734303, 131517548, 249598727, 540742895, 404616118, 549711709, 983715865, 1910489463, 3070327312
Offset: 3

Views

Author

Sascha Kurz, Jun 09 2006

Keywords

Examples

			a(3)=448 because there are 448 polyiamonds consisting of 10 triangles;
a(4)=4655 because there are 4655 polyominoes consisting of 10 squares.

Links

Crossrefs

Cf. A000577, A000104, A000105, A000228, A103465 - A103473, A103465, A120102, A120103.

A103466 Number of polyominoes consisting of n regular unit octagons.

Original entry on oeis.org

1, 1, 3, 11, 50, 269, 1605, 10102, 65323, 430302, 2868320, 19299334, 130807068, 892075515, 6115673262
Offset: 1

Views

Author

Sascha Kurz, Feb 07 2005

Keywords

Links

Crossrefs

Cf. A000577, A000104, A000228, A103465, A103465, A103467, A103468.
Cf. A000577, A000104, A000228, A103465, A103467, A103468, A103469, A103470, A103471, A103472, A103473, A115071, A120102, A120103, A120104.

Extensions

More terms from Sascha Kurz, Jun 09 2006
Definition corrected by John Mason and Sascha Kurz, Sep 20 2020

A103467 Number of polyominoes consisting of n regular unit 9-gons.

Original entry on oeis.org

1, 1, 3, 14, 82, 585, 4418, 34838, 280014, 2285047, 18838395, 156644526, 1311575691
Offset: 1

Views

Author

Sascha Kurz, Feb 07 2005

Keywords

Links

Crossrefs

Cf. A000577, A000104, A000228, A103465, A103466, A103468, A103469, A103470, A103471, A103472, A103473, A115071, A120102, A120103, A120104.

Extensions

More terms from Sascha Kurz, Jun 09 2006
Definition corrected by John Mason and Sascha Kurz, Sep 20 2020

A103464 Number of polyominoes consisting of n regular unit heptagons.

Original entry on oeis.org

1, 1, 2, 7, 25, 118, 558, 2876, 14982, 80075, 431889, 2354991, 12930257, 71459124, 396978189, 2215609864
Offset: 3

Views

Author

Sascha Kurz, Jun 09 2006

Keywords

Links

Crossrefs

Cf. A000577, A000104, A000228, A103466, A103467, A103468, A103469, A103470, A103471, A103472, A103473, A120102, A120103, A120104.
Showing 1-7 of 7 results.

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

Content is available under The OEIS End-User License Agreement.