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 A127440 #12 Oct 07 2017 07:29:47 %S A127440 -2,0,1,-1,2,-2,1,0,1,-2,1,-1,2,0,-1,-1,1,-1,1,1,0,-2,1,0,1,-1,0,-1,0, %T A127440 0,1,1,0,0,-1,-1,2,0,-1,-1,0,0,1,0,1,-2,1,0,0,1,-1,-1,1,1,-1,1,0,-2,1, %U A127440 -1,2,-1,0,1,-2,0,1,1,-2,0,1,-1,2,-1,0,1,-2,0,1,0,1,-2,1,1,0,0,-1,-1,1,1,-1,1,0,0,-1,-1,1,0,0,-1,0,0,1,-1,2 %N A127440 First differences of A008683. %C A127440 Average value is 0, in the sense that lim (a(1)+a(2)+...+a(n))/n = 0. - _Charles R Greathouse IV_, Jan 24 2013 %H A127440 Antti Karttunen, <a href="/A127440/b127440.txt">Table of n, a(n) for n = 1..20000</a> %t A127440 Array[MoebiusMu, 77] // Differences (* _Jean-François Alcover_, Jan 24 2013 *) %o A127440 (PARI) a(n)=moebius(n+1)-moebius(n) \\ _Charles R Greathouse IV_, Jan 24 2013 %Y A127440 Cf. A008683. %K A127440 sign %O A127440 1,1 %A A127440 _Gary W. Adamson_, Jan 14 2007 %E A127440 More terms from _Antti Karttunen_, Oct 07 2017