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%I #7 Mar 30 2012 16:48:52
%S 3,0,0,0,36,72,-72,0,711,1080,144,-2556,12852,23004,-504,-21192,
%T 122877,525996,69366,-531576,1970154,7833756,6613164,-12953124,
%U 24243261,137623572,130318974,-138059232,115953372,2338653528
%N Low-temperature susceptibility expansion for hexagonal lattice (Potts model, q=4).
%C The hexagonal lattice is the familiar 2-dimensional lattice in which each point has 6 neighbors. This is sometimes called the triangular lattice.
%H I. Jensen, <a href="/A057387/b057387.txt">Table of n, a(n) for n = 0..53</a> (from link below)
%H I. Jensen, <a href="http://www.ms.unimelb.edu.au/~iwan/potts/series/trp4sus.ser">More terms</a>
%H G. Nebe and N. J. A. Sloane, <a href="http://www.math.rwth-aachen.de/~Gabriele.Nebe/LATTICES/A2.html">Home page for hexagonal (or triangular) lattice A2</a>
%Y Cf. A057374-A057405.
%K sign
%O 0,1
%A _N. J. A. Sloane_, Aug 30 2000