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 A120386 #2 Mar 30 2012 17:25:49 %S A120386 0,3,17,66,189,589,1677,3829,7948,15649,25543,26931,15472 %N A120386 Number of isomers of polyhex hydrocarbons with C_(2h) symmetry with nineteen hexagons. %C A120386 See Table 4 column 3 on page 615 of the paper by Caporossi and Hansen. Also the sequence starts for the hydrocarbon C_54H_18. If the number of carbons is an odd number then the number of isomers with this symmetry is zero. %D A120386 G. Caporossi and P. Hansen, "Enumeration of Polyhex Hydrocarbons to h=21", J. Chem. Inf. Comput. Sci., vol. 38 (1998) pp. 610-619. %e A120386 If the number of carbons is 56 then the number of isomers of polyhex hydrocarbons with C_(2h) symmetry with nineteen hexagons is 3 which is the third term in the sequence. %Y A120386 Cf. A018190. %K A120386 nonn %O A120386 54,2 %A A120386 _Parthasarathy Nambi_, Aug 27 2006