%I M1105 #23 Jan 08 2019 03:05:17
%S 1,2,4,8,15,28,50,90,156,274,466,804,1348,2300,3804,6450,10547,17784,
%T 28826,48464,77689,130868,207308,350014,548271,931584,1433966,2469368,
%U 3725257,6510384,9590838,17192714,24357702,45428434,61388268,119938514,152169019,320596894,366032458,863591282,863729021,2341276788,1916799026,6556348906,3755360368,18610776960,6082131438,53874179752,1495903344,164440159702,-48816119038,507516102724,-288652716240,1605880660392,-1407950918758
%N Bond percolation series for square lattice.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H I. Jensen, <a href="/A006727/b006727.txt">Table of n, a(n) for n = 0..171</a> (from link below)
%H J. Blease, <a href="http://dx.doi.org/10.1088/0022-3719/10/7/003">Series expansions for the directed-bond percolation problem</a>, J. Phys C vol 10 no 7 (1977), 917-924.
%H I. G. Enting, A, J. Guttmann and I. Jensen, <a href="https://arxiv.org/abs/hep-lat/9410005">Low-Temperature Series Expansions for the Spin-1 Ising Model</a>, arXiv:hep-lat/9410005, 1994; J. Phys. A. 27 (1994) 6987-7006.
%H J. W. Essam, A. J. Guttmann and K. De'Bell, <a href="http://dx.doi.org/10.1088/0305-4470/21/19/018">On two-dimensional directed percolation</a>, J. Phys. A 21 (1988), 3815-3832.
%H J. W. Essam et al., <a href="http://dx.doi.org/10.1103/PhysRevB.33.1982">Analysis of extended series for bond percolation on the directed square lattice</a>, Phys. Rev. B 33 (1986), 1982-1986.
%H I. Jensen, <a href="https://web.archive.org/web/20070613023005/http://www.ms.unimelb.edu.au/~iwan/dirperc/series/sqbcs.ser">More terms</a> [Archived website]
%H Iwan Jensen, Anthony J. Guttmann, <a href="http://arxiv.org/abs/cond-mat/9509121">Series expansions of the percolation probability for directed square and honeycomb lattices</a>, arXiv:cond-mat/9509121, 1995; J. Phys. A 28 (1995), no. 17, 4813-4833.
%K sign,nice
%O 0,2
%A _N. J. A. Sloane_, _Simon Plouffe_