A006741 Series for second parallel moment of hexagonal lattice. (Formerly M4269)

0, 6, 60, 314, 1240, 4166, 12600, 35324, 93576, 236944, 578764, 1371478, 3169380, 7165478, 15901324, 34705018, 74661832, 158529158, 332756408, 691084378, 1421836528, 2899678894, 5867341452, 11784640984, 23512608484

Offset

0,2

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

I. Jensen, Table of n, a(n) for n = 0..82 (from link below)

I. G. Enting, A, J. Guttmann and I. Jensen, Low-Temperature Series Expansions for the Spin-1 Ising Model, J. Phys. A. 27 (1994) 6987-7006.

J. W. Essam, A. J. Guttmann and K. De'Bell, On two-dimensional directed percolation, arXiv:hep-lat/9410005, 1994; J. Phys. A 21 (1988), 3815-3832.

I. Jensen, More terms

Iwan Jensen, Anthony J. Guttmann, Series expansions of the percolation probability for directed square and honeycomb lattices, arXiv:cond-mat/9509121, 1995; J. Phys. A 28 (1995), no. 17, 4813-4833.

G. Nebe and N. J. A. Sloane, Home page for hexagonal (or triangular) lattice A2

Crossrefs

Sequence in context: A296317 A292061 A074441 * A120573 A260345 A028244

Adjacent sequences: A006738 A006739 A006740 * A006742 A006743 A006744

Keyword

nonn

Author

N. J. A. Sloane, Simon Plouffe

Status

approved