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 A247580 #4 Sep 20 2014 14:11:08 %S A247580 2,3,8,10,6,42,16,9,20,110,24,156,84,30,64,136,18,20,40 %N A247580 Base-19 state complexity of partitioned deterministic finite automaton (PDFA) for the periodic sequence (123...n)*. %H A247580 Klaus Sutner and Sam Tetruashvili, <a href="http://www.cs.cmu.edu/~sutner/papers/auto-seq.pdf">Inferring automatic sequences</a> (see table on the p. 5). %Y A247580 Cf. similar sequences listed in A247566 %K A247580 nonn,more %O A247580 2,1 %A A247580 _Vincenzo Librandi_, Sep 20 2014