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%I #10 Aug 16 2021 13:56:51
%S 1,7,31,101,272,636,1340,2600,4725,8135,13391,21217,32536,48496,70512,
%T 100296,139905,191775,258775,344245,452056,586652,753116,957216,
%U 1205477,1505231,1864695,2293025,2800400,3398080,4098496,4915312
%N Column 3 of triangle A055898.
%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_3 for square lattices of Section 6).
%F G.f.: x^3(1+2x+4x^2+2x^3+x^4)/((1-x)^7(1+x)^2). [Corrected by _Georg Fischer_, Aug 16 2021]
%t CoefficientList[Series[(1+2*x+4*x^2+2*x^3+x^4)/((1-x)^7*(1+x)^2), {x, 0, 40}], x] (* _Georg Fischer_, Aug 16 2021 *)
%Y Cf. A055898 (triangle), A055900 (column 4), A055901 (5), A055902 (6), A055903 (7), A055904 (8).
%K nonn,easy
%O 3,2
%A _Christian G. Bower_, Jun 13 2000