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 A064577 #6 Feb 24 2020 17:16:24 %S A064577 0,0,1,0,1,0,2,1,1,0,3,0,1,1,4,0,3,0,4,1,1,0,6,1,1,2,4,0,4,0,6,1,1,1, %T A064577 9,0,1,1,7,0,5,0,5,3,1,0,11,1,3,1,6,0,6,1,8,1,1,0,12,0,1,3,11,1,5,0,8, %U A064577 1,4,0,17,0,1,3,8,1,6,0,15,4,1,0,17,1,1,1,13,0,11,1,10,1,1,1,21,0,3,4,16 %N A064577 First differences of A064574. %C A064577 Apparently a(n)=0 when n+1 is prime. Diverges from A028422(n+1) at n=19. %H A064577 Antti Karttunen, <a href="/A064577/b064577.txt">Table of n, a(n) for n = 1..16383</a> %F A064577 a(n) = A064574(n+1) - A064574(n). - _Antti Karttunen_, Feb 24 2020 %Y A064577 Cf. A064572, A064573, A064574, A064575, A064576, A028422. %K A064577 easy,nonn,look %O A064577 1,7 %A A064577 _Marc LeBrun_, Sep 20 2001