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 A089991 #5 Mar 30 2012 17:34:14
%S A089991 0,0,6,8,0,24,28,32,0,60,0,0,104,112,120,128,0,180,0,240,252,0,322,
%T A089991 336,0,0,0,448,464,480,496,512,0,612,0,720,0,0,858,0,984,1008,0,1144,
%U A089991 1170,0,0,0,1372,0,0,1560,1590,1620,0,0,0,0,1888,1920,1952,1984,2016,2048,0
%N A089991 Maximum lengths of chaotic walks based on the A004001 sequence.
%F A089991 a(n) = MaximumLength[ nested n walk based on A004001[n]*(-1)^A004001[n]+lastsum]
%t A089991 Conway[n_Integer?Positive] := Conway[n] =Conway[Conway[n-1]] + Conway[n - Conway[n-1]] Conway[1] = Conway[2] = 1 digits=200 b=Table[(-1)^Conway[n]*Conway[n], {n, 1, digits}] ChaosWalk[n_Integer?Positive] := NestList[(#+b[[n]])&, 0, n] ChaosWalk[1]=0 a=Table[Max[ChaosWalk[n]], {n, 1, digits}]
%Y A089991 Cf. A004001, A089990.
%K A089991 nonn
%O A089991 1,3
%A A089991 _Roger L. Bagula_, Jan 14 2004