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 A255822 #17 Mar 10 2015 12:58:20
%S A255822 0,1,1,3,5,9,19,41,84,163,311,615,1268,2612,5228,10244,20172,40496,
%T A255822 82066,165284,329388,654207,1305709,2620890,5262399,10524162,20983533,
%U A255822 41878200,83848212,168188942,337036806,673896773,1345770393,2688442850,5375471835
%N A255822 Number of nonzero terms in A117943 up to index 2^n: a(n) = Sum_{k=1..2^n} A117943(k).
%C A255822 The sequence seems to grow roughly as a(n) ~ c*2^n with c = 0.313...
%H A255822 Hiroaki Yamanouchi, <a href="/A255822/b255822.txt">Table of n, a(n) for n = 0..2000</a>
%o A255822 (PARI) N=1;s=0;for(n=1,9e9,s+=A117943(n);n<N&&next;print1(s",");N*=2)
%Y A255822 Cf. A117943, A178931.
%K A255822 nonn
%O A255822 0,4
%A A255822 _M. F. Hasler_, Mar 09 2015
%E A255822 a(25)-a(34) from _Hiroaki Yamanouchi_, Mar 10 2015