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 A094114 #18 Jun 17 2022 03:41:57
%S A094114 0,1,0,2,1,2,0,1,0,4,3,4,2,3,2,4,3,4,0,1,0,2,1,2,0,1,0,8,7,8,6,7,6,8,
%T A094114 7,8,4,5,4,6,5,6,4,5,4,8,7,8,6,7,6,8,7,8,0,1,0,2,1,2,0,1,0,4,3,4,2,3,
%U A094114 2,4,3,4,0,1,0,2,1,2,0,1,0,16,15,16,14,15,14,16,15,16,12,13,12,14,13,14,12
%N A094114 a(n) = -Sum_{i=1..n-1} (-1)^i*2^valuation(i,3).
%H A094114 Rémy Sigrist, <a href="/A094114/b094114.txt">Table of n, a(n) for n = 1..6561</a>
%H A094114 Robert Ferréol (MathCurve), <a href="https://mathcurve.com/fractals/cantor/cantor.shtml">Cantor's (ternary) set</a> [in French]
%p A094114 a:= n-> -add((-1)^i*2^padic[ordp](i, 3), i=1..n-1):
%p A094114 seq(a(n), n=1..100); # _Alois P. Heinz_, Jan 05 2021
%t A094114 a[n_] := Sum[(-1)^(i+1) * 2^IntegerExponent[i, 3], {i, 1, n-1}]; Array[a, 100] (* _Amiram Eldar_, Jun 17 2022 *)
%o A094114 (PARI) a(n)=-sum(i=1,n-1,(-1)^i*2^valuation(i,3))
%Y A094114 Cf. A007949, A093347.
%K A094114 nonn
%O A094114 1,4
%A A094114 _Benoit Cloitre_, May 03 2004