This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A121964 #4 Mar 30 2012 17:25:49 %S A121964 1,13,45,188,587,1588,4547,11377,24111,47515,85645,124260,117943 %N A121964 Number of benzenoids with 21 hexagons, C_(2h) symmetry and containing 2n carbon atoms. %C A121964 See Table 4 column 6 of Brinkmann et al. paper. %D A121964 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 A121964 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 A121964 nonn %O A121964 30,2 %A A121964 _Parthasarathy Nambi_, Sep 10 2006