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A006731
Site percolation series for square lattice.
(Formerly M1055)
3
1, 2, 4, 7, 12, 20, 33, 53, 85, 133, 210, 322, 505, 759, 1192, 1748, 2782, 3931, 6476, 8579, 15216, 17847, 36761, 33612, 93961, 47282, 262987, -16105, 827382, -571524, 2936705, -3661626, 11507775, -18880652, 48169220, -90436605
OFFSET
0,2
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..158 (from link below)
J. W. Essam, A. J. Guttmann and K. De'Bell, On two-dimensional directed percolation, J. Phys. A 21 (1988), 3815-3832.
Iwan 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.
CROSSREFS
Cf. A056532.
Sequence in context: A289115 A342528 A126348 * A222036 A000071 A179111
KEYWORD
sign
STATUS
approved