%I #4 Mar 30 2012 17:25:49

%S 1,13,45,188,587,1588,4547,11377,24111,47515,85645,124260,117943

%N Number of benzenoids with 21 hexagons, C_(2h) symmetry and containing 2n carbon atoms.

%C See Table 4 column 6 of Brinkmann et al. paper.

%D G. Brinkmann, G. Caporossi and P. Hansen, "A survey and new results on computer enumeration of polyhex and fusene hydrocarbons", J. Chem. Inf. Comput. Sci., vol. 43 (2003), pp. 842-851.

%e If n=30 then the number of benzenoids with 21 hexagons with C_(2h) symmetry is 1 which is the first term in the sequence.

%K nonn

%O 30,2

%A _Parthasarathy Nambi_, Sep 10 2006