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 A213949 #9 Jun 01 2014 03:35:17 %S A213949 1,4,10,18,36,57,77,110,141,177,232,270,337,402,453,566,610,721 %N A213949 One half of largest prime gap up to 10^n. %C A213949 Row lengths of A213930. %H A213949 <a href="/index/Pri#gaps">Index entries for primes, gaps between</a> %F A213949 a(n) = A038460(n)/2. %Y A213949 Cf. A213930, A038460. %K A213949 nonn,hard,more %O A213949 1,2 %A A213949 _Washington Bomfim_, Jun 26 2012