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 A055908 #6 Aug 17 2021 02:48:15 %S A055908 1,4,10,21,39,67,107,163,238,337,463,622,818,1058,1346,1690,2095,2570, %T A055908 3120,3755,4481,5309,6245,7301,8484,9807,11277,12908,14708,16692, %U A055908 18868,21252,23853,26688,29766,33105,36715,40615,44815,49335,54186 %N A055908 Column 2 of triangle A055907. %H A055908 A. J. Guttmann, <a href="https://doi.org/10.1016/S0012-365X(99)00262-9">Indicators of solvability for lattice models</a>, Discrete Math., 217 (2000), 167-189 (H_2 for hexagonal lattices of Section 6). %F A055908 G.f.: x^2*(1 + x + x^3)/((1 - x)^5*(1+x)^2*(1 + x^2)). %Y A055908 Cf. A055907. %K A055908 nonn %O A055908 2,2 %A A055908 _Christian G. Bower_, Jun 14 2000