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 A241418 #8 Aug 08 2014 14:46:49 %S A241418 1,1,-2,2,-1,1,-2,1,1,-1,-1,2,-2,1,-1,2,-1,1,-2,1,1,-1,-1,1,1,-2,1,-1, %T A241418 2,-1,1,-2,2,-1,-1,2,-2,1,1,-1,-1,1,1,-2,2,-1,-1,2,-2,1,-1,2,-1,1,-2, %U A241418 1,1,-1,-1,1,1,-2,1,-1,2,-1,1,-2,2,-1,-1,1,1,-2 %N A241418 First differences of Arshon's sequence, cf. A099054. %C A241418 Also first differences of A219762; %C A241418 a(n) = A099054(n+1) - A099054(n) = A219762(n+2) - A219762(n+1). %H A241418 Reinhard Zumkeller, <a href="/A241418/b241418.txt">Table of n, a(n) for n = 0..10000</a> %o A241418 (Haskell) %o A241418 a241418 n = a241418_list !! n %o A241418 a241418_list = zipWith (-) (tail a099054_list) a099054_list %Y A241418 Cf. A099054, A219762. %K A241418 sign %O A241418 0,3 %A A241418 _Reinhard Zumkeller_, Aug 08 2014