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A082392 Expansion of (1/x) * sum(k>=0, x^2^k/(1-2x^2^(k+1))). 3

%I

%S 1,1,2,1,4,2,8,1,16,4,32,2,64,8,128,1,256,16,512,4,1024,32,2048,2,

%T 4096,64,8192,8,16384,128,32768,1,65536,256,131072,16,262144,512,

%U 524288,4,1048576,1024,2097152,32,4194304,2048,8388608,2,16777216

%N Expansion of (1/x) * sum(k>=0, x^2^k/(1-2x^2^(k+1))).

%H R. Stephan, <a href="/somedcgf.html">Some divide-and-conquer sequences ...</a>

%H R. Stephan, <a href="/A079944/a079944.ps">Table of generating functions</a>

%F a(0) = 1, a(2*n) = 2^n, a(2*n+1) = a(n).

%F a(n) = 2^A025480(n) = 2^(A003602(n)-1).

%F a((2*n+1)*2^p-1) = 2^n, p >= 0 and n >= 0. - _Johannes W. Meijer_, Feb 11 2013

%p nmax := 48: for p from 0 to ceil(simplify(log[2](nmax))) do for n from 0 to ceil(nmax/(p+2))+1 do a((2*n+1)*2^p-1) := 2^n od: od: seq(a(n), n=0..nmax); # _Johannes W. Meijer_, Feb 11 2013

%o (PARI) for(n=0, 50, l=ceil(log(n+1)/log(2)); t=polcoeff(sum(k=0, l, (x^2^k)/(1-2*x^2^(k+1)))/x + O(x^(n+1)), n); print1(t", ");) ;

%Y Cf. A045654, A220466.

%K nonn,easy

%O 0,3

%A _Ralf Stephan_, Jun 07 2003

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Last modified March 25 07:12 EDT 2019. Contains 321468 sequences. (Running on oeis4.)