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%I #7 Mar 30 2012 16:48:52
%S 1,0,0,0,0,0,2,0,0,0,6,6,-8,0,36,36,-42,-60,272,330,-402,-554,1758,
%T 3564,-3320,-7056,14616,33426,-21498,-83640,111856,354612,-158802,
%U -884208,758088,3744582,-734260,-9805608,4839270,38734736,2364180
%N Low-temperature partition function expansion for hexagonal lattice (Potts model, q=3).
%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="/A057385/b057385.txt">Table of n, a(n) for n = 0..69</a> (from link below)
%H I. Jensen, <a href="http://www.ms.unimelb.edu.au/~iwan/potts/series/trp3pf.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 0,7
%A _N. J. A. Sloane_, Aug 30 2000