%I M4162 N1730 #19 Mar 03 2021 06:45:36
%S 1,6,24,90,318,1098,3696,12270,40224,130650,421176,1348998,4299018,
%T 13635630,43092888,135698970,426144654,1334488074,4170038328,
%U 13001153910,40464412482,125706293478,389962873920,1207855307874,3736709089176,11544946664622,35633199126576
%N High-temperature series for susceptibility for the spin-1/2 Ising model on hexagonal lattice.
%C Previous name was: Susceptibility for hexagonal lattice.
%C The hexagonal lattice is the familiar 2-dimensional lattice in which each point has 6 neighbors. This is sometimes called the triangular lattice.
%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%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>
%H M. F. Sykes, D. G. Gaunt, P. D. Roberts and J. A. Wyles, <a href="https://doi.org/10.1088/0305-4470/5/5/004">High temperature series for the susceptibility of the Ising model, I. Two dimensional lattices</a>, J. Phys. A 5 (1972) 624-639.
%F a(n) = A002910(2*n), cf. A002920. - _Andrey Zabolotskiy_, Mar 01 2021
%Y Cf. A002910, A002920, A047709.
%K nonn,nice
%O 0,2
%A _N. J. A. Sloane_
%E New name and more terms using A002920 from _Andrey Zabolotskiy_, Mar 03 2021