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 A121973 #4 Mar 30 2012 17:25:49 %S A121973 1,10,187,2802,35384,388936,3862098,35475697,306558871,2521963738 %N A121973 Number of isomeric aza-benzenoids with six nitrogen atoms. %D A121973 N. Trinajstich, Z. Jericevic, J. V. Knop, W. R. Muller and K. Szymanski, "Computer generation of isomeric structures", Pure and Appl. Chem., vol. 55 (1983) pp. 379-390. %e A121973 If n=5 then the number of isomeric aza-benzenoids with six nitrogen atoms is 35384. Here n is the number of hexagons. %K A121973 nonn %O A121973 1,2 %A A121973 _Parthasarathy Nambi_, Sep 05 2006