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 A175007 #2 Mar 30 2012 18:57:11 %S A175007 1,2,3,5,6,9,11,12,14,17,18,20,22,25,26,29,30,33,34,36,38,40,42,45,47, %T A175007 48,50,52,54,57,58,60,62,64,66,69,70,73,74,76,78,80,82,84,86,89,91,93, %U A175007 95,96,98,100,102,104,106,109,110,112,114,116,118,120,122,124,126,128 %N A175007 Positions of nonnegative terms in A131389. %C A175007 Is a(n+1)-a(n) always 1,2 or 3? %e A175007 The first 20 terms of A131389 are %e A175007 0,1,2,-1,3,4,-2,-3,6,-4,5,7,-5,8,-6,-7,9,10,-8,11. %e A175007 Positions occupied by nonnegatives are %e A175007 1,2,3,5,6,9,11,12,14,17,18,20. %Y A175007 Cf. A131389, A175008. %K A175007 nonn %O A175007 1,2 %A A175007 _Clark Kimberling_, Apr 03 2010