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 A129019 #3 Mar 30 2012 16:50:41 %S A129019 1,4,19,70,239,726,2062 %N A129019 A129017(3n+1). %D A129019 J. R. Dias, The Periodic Table Set as a Unifying Concept in Going from Benzenoid Hydrocarbons to Fullerene Carbons, in "The Periodic Table: Into the 21st Century", Edited by D. H. Rouvray and R. B. King, Research Studies Press Ltd, Baldock, Hertfordshire, England, 2004, 371-396. %Y A129019 Cf. A129012-A129021. %K A129019 nonn %O A129019 0,2 %A A129019 _N. J. A. Sloane_, based on email from Jerry R. Dias (DiasJ(AT)umkc.edu), May 08 2007