This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A002919 M4162 N1730 #19 Mar 03 2021 06:45:36 %S A002919 1,6,24,90,318,1098,3696,12270,40224,130650,421176,1348998,4299018, %T A002919 13635630,43092888,135698970,426144654,1334488074,4170038328, %U A002919 13001153910,40464412482,125706293478,389962873920,1207855307874,3736709089176,11544946664622,35633199126576 %N A002919 High-temperature series for susceptibility for the spin-1/2 Ising model on hexagonal lattice. %C A002919 Previous name was: Susceptibility for hexagonal lattice. %C A002919 The hexagonal lattice is the familiar 2-dimensional lattice in which each point has 6 neighbors. This is sometimes called the triangular lattice. %D A002919 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). %D A002919 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A002919 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 A002919 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 A002919 a(n) = A002910(2*n), cf. A002920. - _Andrey Zabolotskiy_, Mar 01 2021 %Y A002919 Cf. A002910, A002920, A047709. %K A002919 nonn,nice %O A002919 0,2 %A A002919 _N. J. A. Sloane_ %E A002919 New name and more terms using A002920 from _Andrey Zabolotskiy_, Mar 03 2021