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 A190884 #4 Mar 30 2012 18:57:29 %S A190884 3,7,11,15,20,24,28,32,37,41,45,49,53,54,58,62,66,70,75,79,83,87,92, %T A190884 96,100,104,109,113,117,121,125,126,130,134,138,142,147,151,155,159, %U A190884 164,168,172,176,181,185,189,193,197,198,202,206,210,214,219,223,227,231,236,240,244,248,253,257,261,265,269,270,274,278,282,286 %N A190884 Positions of 2 in A189480. %C A190884 A sequence in a 4-way partition of the natural numbers. See A189480. %t A190884 (See A189480.) %Y A190884 Cf. A189480. %K A190884 nonn %O A190884 1,1 %A A190884 _Clark Kimberling_, May 23 2011