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%I #12 Nov 11 2023 01:16:51
%S 0,0,1,1,9,12,39,61,178,274,796,1251,3578,5692,16290,26069,74980,
%T 120676,348564,563503,1635175,2652445,7729807,12574028,36784467,
%U 59975232,176063801,287613473,846967739,1385815492,4092516853,6705360813,19852731854,32565589836,96642900684
%N Number of free hexagonal polygons of symmetry class C_(2v) and area n.
%H Markus Vöge, Anthony J. Guttmann and Iwan Jensen, <a href="https://doi.org/10.1021/ci010098g">On the number of benzenoid hydrocarbons</a>, J. Chem. Inf. Comput. Sci., (2002), vol. 42, 456-466. See Table 3 under the column C_(2c) [sic. This is a typo, should be C_(2v) instead].
%K nonn
%O 1,5
%A _Parthasarathy Nambi_, Aug 19 2006
%E More terms from _N. J. A. Sloane_, Aug 27 2006
%E Name corrected by _Andrey Zabolotskiy_, Nov 10 2023