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%I #6 Aug 17 2021 02:48:15
%S 1,4,10,21,39,67,107,163,238,337,463,622,818,1058,1346,1690,2095,2570,
%T 3120,3755,4481,5309,6245,7301,8484,9807,11277,12908,14708,16692,
%U 18868,21252,23853,26688,29766,33105,36715,40615,44815,49335,54186
%N Column 2 of triangle A055907.
%H 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 G.f.: x^2*(1 + x + x^3)/((1 - x)^5*(1+x)^2*(1 + x^2)).
%Y Cf. A055907.
%K nonn
%O 2,2
%A _Christian G. Bower_, Jun 14 2000