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 A191777 #4 Mar 30 2012 18:57:33 %S A191777 1,3,5,6,8,10,12,14,15,17,19,20,21,23,25,26,28,30,32,33,35,36,38,40, %T A191777 41,43,45,47,49,50,52,54,55,57,59,60,62,64,66,68,70,71,73,75,77,78,80, %U A191777 82,83,85,87,89,91,93,95,96,98,100,102,104,105,107,109,110 %N A191777 Positions of 1 in A020903; complement of A020904. %C A191777 See A020903. %t A191777 (See A020903.) %Y A191777 Cf. A020903, A020904. %K A191777 nonn %O A191777 1,2 %A A191777 _Clark Kimberling_, Jun 16 2011