A090673 - OEIS

%I #22 Jun 11 2022 03:33:34

%S 1,0,0,1,0,0,0,1,3,4,3,3,11,24,8,-91,-261,-290,254,1671,3127,786,

%T -13939,-49052,-80276,21450,515846,1411017,1160761,-4793764,-20340586,

%U -29699360,33165914,256169433,495347942,-127736296,-3068121066,-7092358808,-1024264966,35697720501,91243390558,25789733672,-420665229170,-1089052872105,-238516756366,5101697398582,12146149238921

%N Large-q series expansion for exponential of bulk free energy of the square-lattice zero-temperature Potts antiferromagnet, divided by (q-1)^2/q, in terms of the variable z = 1/(q - 1).

%C Related to chromatic polynomial of the infinite square grid.

%D N. Biggs, Algebraic Graph Theory, Cambridge, 2nd. Ed., 1993, p. 96.

%H Andrey Zabolotskiy, <a href="/A090673/b090673.txt">Table of n, a(n) for n = 0..79</a> (from Jacobsen 2010)

%H Jesper Lykke Jacobsen, <a href="https://doi.org/10.1088/1751-8113/43/31/315002">Bulk, surface and corner free-energy series for the chromatic polynomial on the square and triangular lattices</a>, J. Phys. A: Math. Theor., 43 (2010), 315002; arXiv:<a href="https://arxiv.org/abs/1005.3609">1005.3609</a> [cond-mat.stat-mech], 2010.

%H D. Kim and I. G. Enting, <a href="https://doi.org/10.1016/0095-8956(79)90008-X">The limit of chromatic polynomials</a>, J. Combin. Theory B26 (1979), 327-336.

%H J. Salas and A. D. Sokal, <a href="http://arxiv.org/abs/0711.1738">Transfer Matrices and Partition-Function Zeros for Antiferromagnetic Potts Models. V. Further Results for the Square-Lattice Chromatic Polynomial</a>, J. Stat. Phys. 135 (2009) 279-373, arXiv:0711.1738 [cond-mat.stat-mech], 2007-2009.

%Y Cf. A238835, A238836.

%K sign

%O 0,9

%A _N. J. A. Sloane_, Dec 18 2003

%E More terms from Salas-Sokal, 2009. - _N. J. A. Sloane_, Mar 14 2014

%E Name corrected by _Andrey Zabolotskiy_, Feb 11 2022