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 A151930 #12 Feb 28 2017 07:45:40
%S A151930 1,0,2,-2,2,0,4,-6,2,0,4,-4,4,0,8,-14,2,0,4,-4,4,0,8,-12,4,0,8,-8,8,0,
%T A151930 16,-30,2,0,4,-4,4,0,8,-12,4,0,8,-8,8,0,16,-28,4,0,8,-8,8,0,16,-24,8,
%U A151930 0,16,-16,16,0,32,-62,2,0,4,-4,4,0,8,-12,4,0,8,-8,8,0,16,-28,4,0,8,-8,8,0,16,-24,8,0,16,-16,16,0,32
%N A151930 First differences of A001316.
%C A151930 Net increase in number of ON cells at generation n of 1-D CA using Rule 90.
%H A151930 <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a>
%F A151930 a((2*n+1)*2^p-1) = (2-2^p) * A001316(n), p >= 0 and n >=0. - _Johannes W. Meijer_, Jan 25 2013
%F A151930 G.f.: -1/x + ((1 - x)/x)*Product_{k>=0} (1 + 2*x^(2^k)). - _Ilya Gutkovskiy_, Feb 28 2017
%p A151930 nmax := 94: A001316 := n -> if n<=-1 then 0 else 2^add(i, i=convert(n, base, 2)) fi: for p from 0 to ceil(log[2](nmax))+1 do for n from 0 to nmax/(p+2)+1 do a((2*n+1)*2^p-1) := (2-2^p) * A001316(n) od: od: seq(a(n), n=0..nmax); # _Johannes W. Meijer_, Jan 25 2013
%Y A151930 Cf. A001316, A220466.
%K A151930 sign
%O A151930 0,3
%A A151930 _N. J. A. Sloane_, Aug 10 2009