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 A071622 #9 Jul 27 2025 11:47:00
%S A071622 1,2,1,2,1,2,3,4,5,6,7,8,7,6,5,6,7,8,7,8,7,6,7,6,5,6,5,6,7,8,7,6,7,8,
%T A071622 7,6,5,6,7,8,9,10,11,12,11,10,9,10,11,10,9,8,7,8,7,8,7,8,9,10,9,8,9,8,
%U A071622 9,8,7,6,7,8,9,10,11,12,13,14,15,14,15,14,13,12,13,12,13,12,11,10,9,10,9
%N A071622 a(n) = (-1)*Sum_{k=1..n} (-1)^floor((4/3)^k).
%C A071622 Conjecture: for n>2300, a(n) > log(n)^2.
%t A071622 Table[(-1)Sum[(-1)^Floor[(4/3)^k],{k,n}],{n,100}] (* _Harvey P. Dale_, Jul 27 2025 *)
%o A071622 (PARI) for(n=1,100,print1(-sum(i=1,n,sign((-1)^floor((4/3)^i))),","))
%Y A071622 Cf. A071532.
%K A071622 easy,nonn
%O A071622 1,2
%A A071622 _Benoit Cloitre_, Jun 22 2002