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%I #7 Aug 17 2021 02:48:28
%S 1,8,36,128,388,1050,2601,6013,13141,27416,55012,106816,201685,371828,
%T 671630,1192093,2084360,3597991,6143128,10391369,17439285,29073358,
%U 48199071,79535657,130740732,214230558,350125952,571019573,929690344
%N Column 4 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_4 for hexagonal lattices of Section 6).
%F G.f.: x^4*(1+3x+4x^2+10x^3+12x^4+14x^5+16x^6+13x^7+14x^8+7x^9+6x^10+4x^11+x^13)/ ((1-x)^9*(1+x)^4*(1+x^2)^3*(1-x-x^2)*(1+x+x^2)).
%Y Cf. A055907.
%K nonn
%O 4,2
%A _Christian G. Bower_, Jun 14 2000
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