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%I #16 Aug 12 2018 09:38:21
%S 1,1,2,2,5,5,4,4,13,13,10,7,7,7,8,8,35,35,26,17,8,8,8,8,11,14,17,17,
%T 17,17,16,16,97,97,70,43,16,-11,-11,-11,-11,-11,-2,7,16,25,34,43,43,
%U 43,43,43,43,43,40,37,34,31,31,31,31,31,32,32,275,275,194,113,32,-49,-130,-130,-130,-130,-130
%N a(1) = a(2) = 1; for n >= 3, a(n) = 3*a(t(n)) - a(n-t(n)) where t = A004001.
%C Sequence has a fractal-like structure. Each generation (between consecutive powers of 2) provides a pattern which looks like an EKG signal since maximum value of a(n) (in corresponding generation) is damped step by step.
%H Altug Alkan, <a href="/A317921/b317921.txt">Table of n, a(n) for n = 1..32768</a>
%H Altug Alkan, <a href="/A317921/a317921_1.png">Line plot of a(n) for n <= 2^17</a>
%o (PARI) t=vector(99); t[1]=t[2]=1; for(n=3, #t, t[n] = t[n-t[n-1]]+t[t[n-1]]); a=vector(99); a[1]=a[2]=1; for(n=3, #a, a[n] = 3*a[t[n]]-a[n-t[n]]); a
%Y Cf. A004001, A317648, A317754.
%K sign,look
%O 1,3
%A _Altug Alkan_, Aug 11 2018
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