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 1-8 of 8 results.

A306175 Number of unrooted self-avoiding walks with n steps that can make turns from the set +-Pi/5, +-3*Pi/5.

Original entry on oeis.org

1, 2, 6, 19, 66, 229, 831, 2991, 10859, 39173, 141631, 510079, 1835583, 6586932, 23614821, 84492315, 302014619, 1077860479, 3843695976, 13690026688
Offset: 1

Views

Author

Hugo Pfoertner, Jun 23 2018

Keywords

Comments

The turning angles are those of the regular pentagon, with one vertex corresponding to the forbidden U-turn. The path may neither intersect nor touch itself anywhere.

Crossrefs

Extensions

a(7)-a(9) from Hugo Pfoertner, Dec 23 2018
a(10)-a(20) from Bert Dobbelaere, May 15 2025

A316197 Number of self-avoiding polygons with perimeter 2*n and sides = 1 that have vertex angles from the set +-Pi/7, +-3*Pi/7, +-5*Pi/7, not counting rotations and reflections as distinct.

Original entry on oeis.org

0, 0, 3, 4, 83, 533, 8329
Offset: 1

Views

Author

Hugo Pfoertner, Jun 28 2018

Keywords

Crossrefs

A316198 Number of self-avoiding polygons with perimeter 2*n and sides = 1 that have vertex angles from the set 0, +-Pi/4, +-Pi/2, +-3*Pi/4, not counting rotations and reflections as distinct.

Original entry on oeis.org

0, 2, 6, 59, 695, 12198
Offset: 1

Views

Author

Hugo Pfoertner, Jul 04 2018

Keywords

Comments

Holes are excluded, i.e., the boundary path may nowhere touch or intersect itself.

Crossrefs

A316199 Number of self-avoiding polygons with perimeter 2*n and sides = 1 that have vertex angles from the set +-Pi/9, +-3*Pi/9, +-5*Pi/9, +-7*Pi/9, not counting rotations and reflections as distinct.

Original entry on oeis.org

0, 0, 8, 17, 472, 7042
Offset: 1

Views

Author

Hugo Pfoertner, Jul 04 2018

Keywords

Comments

Holes are excluded, i.e., the boundary path may nowhere touch or intersect itself.

Crossrefs

A316192 Number of self-avoiding polygons with perimeter n and sides = 1 that have vertex angles from the set 0, +-Pi/6, +-*Pi/3, +-Pi/2, +-2*Pi/3, +-5*Pi/6, not counting rotations and reflections as distinct.

Original entry on oeis.org

0, 0, 1, 3, 4, 22, 69, 418, 2210, 14024
Offset: 1

Views

Author

Hugo Pfoertner, Jul 07 2018

Keywords

Comments

Holes are excluded, i.e., the boundary path may nowhere touch or intersect itself.

Crossrefs

A316200 Number of self-avoiding polygons with perimeter n and sides = 1 that have vertex angles from the set 0, +-Pi/5, +-2*Pi/5, +-3*Pi/5, +-4*Pi/5, not counting rotations and reflections as distinct.

Original entry on oeis.org

0, 0, 0, 2, 2, 10, 15, 124, 352, 2378, 19405
Offset: 1

Views

Author

Hugo Pfoertner, Jul 07 2018

Keywords

Comments

Holes are excluded, i.e., the boundary path may nowhere touch or intersect itself.

Crossrefs

A316201 Number of self-avoiding polygons with perimeter 2*n and sides = 1 that have vertex angles from the set +-Pi/11, +-3*Pi/11, +-5*Pi/11, +-7*Pi/11, +-9*Pi/11, not counting rotations and reflections as distinct.

Original entry on oeis.org

0, 0, 8, 19, 720, 10578
Offset: 1

Views

Author

Hugo Pfoertner, Jul 07 2018

Keywords

Comments

Holes are excluded, i.e., the boundary path may nowhere touch or intersect itself.

Crossrefs

A346125 Numbers m such that no self-avoiding walk that can make turns from the set +-Pi/5, +-3*Pi/5, of length m + 1 fits into the smallest circle that can enclose a walk of length m.

Original entry on oeis.org

1, 3, 5, 6, 7, 9, 11, 12, 14, 15, 17, 19, 25, 27, 28, 31, 32, 33, 34, 35, 37, 38, 39, 42, 43, 44, 45, 46, 48, 49, 50, 51, 52, 53, 54, 57, 59
Offset: 1

Views

Author

Hugo Pfoertner and Markus Sigg, Jul 31 2021

Keywords

Comments

Although closed walks (see A316195) would be allowed, no closed walk that fits into a smaller enclosing circle than any open walk of the same length is known.

Examples

			See link for illustrations of terms corresponding to diameters D < 5.114.
		

Crossrefs

Cf. A346123-A346132 similar to this sequence with other sets of turning angles.
Showing 1-8 of 8 results.