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 1-10 of 11 results. Next

A001334 Number of n-step self-avoiding walks on hexagonal [ =triangular ] lattice.

Original entry on oeis.org

1, 6, 30, 138, 618, 2730, 11946, 51882, 224130, 964134, 4133166, 17668938, 75355206, 320734686, 1362791250, 5781765582, 24497330322, 103673967882, 438296739594, 1851231376374, 7812439620678, 32944292555934, 138825972053046
Offset: 0

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Author

Keywords

Comments

The hexagonal lattice is the familiar 2-dimensional lattice in which each point has 6 neighbors. This is sometimes called the triangular lattice.

References

  • A. J. Guttmann, Asymptotic analysis of power-series expansions, pp. 1-234 of C. Domb and J. L. Lebowitz, editors, Phase Transitions and Critical Phenomena. Vol. 13, Academic Press, NY, 1989.
  • B. D. Hughes, Random Walks and Random Environments, Oxford 1995, vol. 1, p. 459.
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Programs

  • Mathematica
    mo={{2, 0},{-1, 1},{-1, -1},{-2, 0},{1, -1},{1, 1}}; a[0]=1;
    a[tg_, p_:{{0, 0}}] := Block[{e, mv = Complement[Last[p]+# & /@ mo, p]}, If[tg == 1, Length@mv, Sum[a[tg-1, Append[p, e]], {e, mv}]]];
    a /@ Range[0, 6]
    (* Robert FERREOL, Nov 28 2018; after the program of Giovanni Resta in A001411 *)
  • Python
    def add(L,x):
        M=[y for y in L];M.append(x)
        return(M)
    plus=lambda L,M : [x+y for x,y in zip(L,M)]
    mo=[[2,0],[-1,1],[-1, -1],[-2,0],[1,-1],[1, 1]]
    def a(n,P=[[0, 0]]):
        if n==0: return(1)
        mv1 = [plus(P[-1],x) for x in mo]
        mv2=[x for x in mv1 if x not in P]
        if n==1: return(len(mv2))
        else: return(sum(a(n-1,add(P,x)) for x in mv2))
    [a(n) for n in range(11)]
    # Robert FERREOL, Dec 11 2018

A001337 Number of n-step polygons on f.c.c. lattice.

Original entry on oeis.org

0, 0, 48, 264, 1680, 11640, 86352, 673104, 5424768, 44828400, 377810928, 3235366752, 28074857616, 246353214240, 2182457514960, 19495053028800, 175405981214592
Offset: 1

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Keywords

Comments

Number of n-step closed self-avoiding walks starting at the origin. - Bert Dobbelaere, Jan 14 2019

References

  • B. D. Hughes, Random Walks and Random Environments, Oxford 1995, vol. 1, p. 460.
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Equals 12*A003287(n-1), n > 1.
Equals 2n*A005398(n).
Cf. A001336.

Extensions

a(15)-a(17) from Bert Dobbelaere, Jan 14 2019

A001666 Number of n-step self-avoiding walks on b.c.c. lattice (version 2).

Original entry on oeis.org

1, 8, 56, 392, 2648, 17960, 120056, 804824, 5351720, 35652680, 236291096, 1568049560, 10368669992, 68626647608, 453032542040, 2992783648424, 19731335857592, 130161040083608, 857282278813256, 5648892048530888, 37175039569217672, 244738250638121768
Offset: 0

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Author

Keywords

References

  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Equals twice A002903 except for initial term.

Extensions

a(16)-a(18) from Bert Dobbelaere, Jan 16 2019
Terms a(19) and beyond from Schram et al. added by Andrey Zabolotskiy, Feb 02 2022
Edited by N. J. A. Sloane, Oct 16 2022

A227511 Triangle read by rows: Number of n-step self-avoiding walks on f.c.c. lattice ending at point with x = k.

Original entry on oeis.org

1, 4, 4, 36, 32, 16, 308, 292, 192, 64, 2764, 2672, 2016, 1024, 256, 25404, 24780, 20160, 12480, 5120, 1024, 237164, 232512, 197940, 137472, 71680, 24576, 4096, 2237948, 2201948, 1930944, 1443616, 869376, 390144, 114688, 16384, 21286548, 20997008, 18805488, 14786176
Offset: 0

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Author

Joseph Myers, Jul 14 2013

Keywords

Comments

The number of walks ending with x = -k is the same as the number ending with x = k.

Examples

			Initial rows (paths of length 0, 1, 2, ...):
{ 1 };
{ 4, 4 };
{ 36, 32, 16 };
{ 308, 292, 192, 64 }.
		

Crossrefs

A000765 Number of n-step self-avoiding walks on f.c.c. lattice ending at point with x = 0.

Original entry on oeis.org

1, 4, 36, 308, 2764, 25404, 237164, 2237948, 21286548, 203701772, 1958748676, 18908954324, 183135542956, 1778581016076, 17314029758828, 168891863875652
Offset: 0

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Author

Keywords

References

  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Extensions

Edited and extended by Joseph Myers, Jul 14 2013
a(12)-a(15) from Bert Dobbelaere, Jan 13 2019

A000766 Number of n-step self-avoiding walks on f.c.c. lattice ending at point with x = 1.

Original entry on oeis.org

4, 32, 292, 2672, 24780, 232512, 2201948, 20997008, 201314448, 1938659936, 18737136032, 181646110192, 1765522809468, 17198432462368, 167859941774728
Offset: 1

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Author

Keywords

References

  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Extensions

Edited and extended by Joseph Myers, Jul 14 2013
a(12)-a(15) from Bert Dobbelaere, Jan 13 2019

A000767 Number of n-step self-avoiding walks on f.c.c. lattice ending at point with x = 2.

Original entry on oeis.org

16, 192, 2016, 20160, 197940, 1930944, 18805488, 183156320, 1785303660, 17421627280, 170214459928, 1665089608504, 16307758577692, 159896665015064
Offset: 2

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Author

Keywords

References

  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Extensions

Edited and extended by Joseph Myers, Jul 14 2013
a(12)-a(15) from Bert Dobbelaere, Jan 13 2019

A000768 Number of n-step self-avoiding walks on f.c.c. lattice ending at point with x = 3.

Original entry on oeis.org

64, 1024, 12480, 137472, 1443616, 14786176, 149371964, 1496777088, 14924375156, 148353336272, 1471838989872, 14584911842000, 144423054478680
Offset: 3

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Author

Keywords

References

  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Extensions

Edited and extended by Joseph Myers, Jul 14 2013
a(12)-a(15) from Bert Dobbelaere, Jan 13 2019

A336907 Number of n-step self-avoiding walks on the f.c.c. lattice with no non-contiguous adjacencies.

Original entry on oeis.org

1, 12, 84, 564, 3804, 25308, 167796, 1108452, 7305132, 48043044, 315466884, 2068604028, 13549151244, 88658702484, 579649775796, 3786953782764
Offset: 0

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Author

Sean A. Irvine, Aug 07 2020

Keywords

Crossrefs

Cf. A001336, A174319 (cubic lattice equivalent), A336906 (b.c.c. equivalent).

A213453 Self-avoiding walks on the f.c.c. lattice.

Original entry on oeis.org

1, 6, 66, 702, 7350, 76266, 786858, 8086074, 82848522, 846886962, 8640964782
Offset: 1

Views

Author

N. J. A. Sloane, Jun 12 2012

Keywords

References

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

Crossrefs

Formula

Apparently a(n) = A001336(n-1)/2 for n > 1. - Andrey Zabolotskiy, Dec 29 2018
Showing 1-10 of 11 results. Next