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 A166108 #7 Mar 11 2014 01:32:48 %S A166108 0,1,3,4,2,7,5,6,10,9,8,12,13,14,16,17,18,19,11,15,24,28,27,23,22,21, %T A166108 30,20,25,29,33,31,26,34,32,42,45,36,46,35,48,40,47,39,52,38,37,53,51, %U A166108 55,44,49,41,54,57,63,58,59,43,50,60,72,61,65,64,68,73,69,56,78,66,75,76 %N A166108 a(0)=0. For n >= 1, a(n) = (A084758(n+1)-A084758(n))/2. %C A166108 Is this sequence a permutation of the nonnegative integers? %Y A166108 Cf. A084758 %K A166108 nonn %O A166108 0,3 %A A166108 _Leroy Quet_, Oct 06 2009 %E A166108 Terms beyond a(7) from _R. J. Mathar_, Jan 25 2010