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 A175034 #3 Mar 30 2012 17:40:18 %S A175034 2,5,7,11,12,14,17,18,20,23,27,29,31,32,37,38,40,41,42,44,47,50,51,52, %T A175034 56,57,59,62,65,67,68,69,70,73,74,77,82,83,84,86,87,88,92,95,96,98, %U A175034 101,102,104,107,109,110,112,113,117,119,122,125,126,127,128,131,132,135,137,139 %N A175034 Offsets i such that i + n*(n+1)/2 is never a perfect square for any n>0. %C A175034 Complement of A175035. %Y A175034 Cf. A001108, A006451, A154138, A154139, A154140, A154141 %K A175034 easy,nonn %O A175034 1,1 %A A175034 _Ctibor O. Zizka_, Nov 10 2009 %E A175034 Extended by _R. J. Mathar_, Nov 26 2009