

A006803


Percolation series for hexagonal lattice.
(Formerly M2232)


5



1, 0, 0, 1, 0, 3, 1, 9, 6, 29, 27, 99, 112, 351, 450, 1275, 1782, 4704, 6998, 17531, 27324, 65758, 106211, 247669, 411291, 935107, 1587391, 3535398, 6108103, 13373929, 23438144, 50592067, 89703467, 191306745, 342473589
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OFFSET

0,6


COMMENTS

The hexagonal lattice is the familiar 2dimensional 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..51
J. Blease, Series expansions for the directedbond percolation problem, J. Phys C vol 10 no 7 (1977), 917924.
J. W. Essam, A. J. Guttmann and K. De'Bell, On twodimensional directed percolation, J. Phys. A 21 (1988), 38153832.
I. Jensen, More terms
Iwan Jensen, Anthony J. Guttmann, Series expansions of the percolation probability for directed square and honeycomb lattices, arXiv:condmat/9509121, 1995; J. Phys. A 28 (1995), no. 17, 48134833.
G. Nebe and N. J. A. Sloane, Home page for hexagonal (or triangular) lattice A2


CROSSREFS

Cf. A006809.
Sequence in context: A229759 A185580 A052931 * A197730 A231902 A143495
Adjacent sequences: A006800 A006801 A006802 * A006804 A006805 A006806


KEYWORD

sign


AUTHOR

N. J. A. Sloane


STATUS

approved



