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 1-6 of 6 results.

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

A001336 Number of n-step self-avoiding walks on f.c.c. lattice.

Original entry on oeis.org

1, 12, 132, 1404, 14700, 152532, 1573716, 16172148, 165697044, 1693773924, 17281929564, 176064704412, 1791455071068, 18208650297396, 184907370618612, 1876240018679868, 19024942249966812, 192794447005403916, 1952681556794601732, 19767824914170222996
Offset: 0

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Author

Keywords

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

Extensions

a(15) from Bert Dobbelaere, Jan 13 2019
Terms a(16) and beyond from Schram et al. added by Andrey Zabolotskiy, Feb 02 2022

A336906 Number of n-step self-avoiding walks on the b.c.c. lattice with no non-contiguous adjacencies.

Original entry on oeis.org

1, 8, 56, 296, 1640, 8984, 49256, 266600, 1448072, 7820984, 42316952, 227940584, 1229803016, 6612947048, 35605181720, 191204813288, 1027868658200
Offset: 0

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Author

Sean A. Irvine, Aug 07 2020

Keywords

Crossrefs

Cf. A001666, A174319 (cubic lattice equivalent), A336907 (f.c.c. equivalent).

A002903 Number of n-step self-avoiding walks on b.c.c. lattice (version 1).

Original entry on oeis.org

1, 4, 28, 196, 1324, 8980, 60028, 402412, 2675860, 17826340, 118145548, 784024780, 5184334996, 34313323804, 226516271020, 1496391824212, 9865667928796, 65080520041804, 428641139406628, 2824446024265444, 18587519784608836, 122369125319060884
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 A001666/2 apart from initial term.

Extensions

Edited by N. J. A. Sloane, Oct 16 2022

A001667 2n-step polygons on b.c.c. lattice.

Original entry on oeis.org

96, 1776, 43776, 1237920, 37903776, 1223681760, 41040797376, 1416762272736, 50027402384640, 1799035070369856
Offset: 2

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Author

Keywords

Comments

Number of 2n-step closed self-avoiding walks starting from the origin. - Bert Dobbelaere, Jan 16 2019

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

a(9)-a(10) from Bert Dobbelaere, Jan 16 2019
a(11) from Butera & Comi added by Andrey Zabolotskiy, Jun 02 2022

A260347 Coefficients of the sum of the mean squared distance generating function for the body-centered cubic lattice.

Original entry on oeis.org

3, 48, 531, 5088, 44751, 373404, 2999985, 23457672, 179561859, 1352017596, 10042445889, 73771019064, 536817918837, 3875387231484, 27783517769223, 197998094612568
Offset: 1

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Author

N. J. A. Sloane, Aug 02 2015

Keywords

Crossrefs

Cf. A001666.
Showing 1-6 of 6 results.