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.

A151541 Number of 2-sided triangular strip polyedges with n cells.

Original entry on oeis.org

1, 3, 8, 32, 123, 523, 2201, 9443, 40341, 172649, 736926, 3141607, 13367012, 56790498, 240919918, 1020753475, 4319803799, 18262494912, 77134873774, 325518862387, 1372679840360, 5784417772262
Offset: 1

Views

Author

Ed Pegg Jr, May 13 2009

Keywords

Comments

Also number of unrooted self-avoiding walks of n steps on hexagonal [ =triangular ] lattice. - Hugo Pfoertner, Jun 23 2018

Links

Crossrefs

Cf. A037245, A151539, A151540, A159867, A266925.
Asymptotically approaches (1/24)*A001334(n) for increasing n.

Extensions

a(9)-a(13) from Joseph Myers, Oct 05 2011
a(14)-a(22) from Bert Dobbelaere, Mar 23 2025

A159867 Number of 2-sided n-triangular polyedges.

Original entry on oeis.org

1, 3, 12, 60, 375, 2613, 19074, 143660, 1101860, 8562292, 67206242, 531804577, 4236708679
Offset: 1

Views

Author

Eric W. Weisstein, Apr 24 2009

Keywords

Links

Crossrefs

Cf. A151539, A151540, A151541.

Extensions

a(9) and a(10) from Joseph Myers, Oct 05 2011
a(11)-a(13) from Aaron N. Siegel, May 22 2022

A151539 Number of 1-sided triangular polyedges with n cells.

Original entry on oeis.org

1, 3, 19, 104, 719, 5123, 37936, 286606, 2202201, 17119423, 134401246, 1063570767, 8473332319
Offset: 1

Views

Author

Ed Pegg Jr, May 13 2009

Keywords

Links

Crossrefs

Cf. A151540, A151541, A159867.

Extensions

a(9) and a(10) from Joseph Myers, Oct 05 2011
a(11)-a(13) from Aaron N. Siegel, May 23 2022

A213451 Number of fixed triangular strip polyedges with n edges.

Original entry on oeis.org

3, 15, 69, 309, 1365, 5973, 25941, 112065, 482067, 2066583, 8834469, 37677603, 160367343
Offset: 1

Views

Author

N. J. A. Sloane, Jun 11 2012

Keywords

References

  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

Links

Crossrefs

Cf. A001334, A151540, A151541.

Formula

Apparently, a(n) = A001334(n)/2 for n >= 1. It needs to be clarified whether the objects described by this sequence are equivalent to the self-avoiding walks on the hexagonal lattice together with a restriction on their orientation. - Hugo Pfoertner, Jul 24 2021

Extensions

Better description and more terms from Joseph Myers, Jun 12 2012
Showing 1-4 of 4 results.

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

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