A005551 Number of n-step self-avoiding walks on hexagonal lattice from (0,0) to (0,4).

1, 20, 130, 576, 2218, 8170, 29830, 109192, 402258, 1492746, 5578742, 20986424, 79420122, 302175648, 1155298598, 4436375790, 17103294308, 66174208076, 256870951048, 1000080994758, 3904276709604, 15280413966512

Offset: 4

Author

N. J. A. Sloane

Keywords

• nonn
• walk
• more

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

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

Links

• D. S. McKenzie, The end-to-end length distribution of self-avoiding walks, J. Phys. A 6 (1973), 338-352.
• G. Nebe and N. J. A. Sloane, Home page for hexagonal (or triangular) lattice A2

Crossrefs

Cf. A001335, A003289, A003290, A003291, A005549, A005550, A005552, A005553.

Extensions

More terms and improved title from Sean A. Irvine, Feb 14 2016

a(23)-a(25) from Bert Dobbelaere, Jan 15 2019