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A126656 a(1)=1; for n>1, a(n) = sum{k=1 to n-1} a(k) floor(n/k). 0
1, 2, 5, 13, 27, 62, 125, 266, 538, 1106, 2213, 4509, 9019, 18166, 36365, 73012, 146025, 292658, 585317, 1171783, 2343697, 4689610, 9379221, 18763300, 37526628, 75062278, 150125100, 300268507, 600537015, 1201111598, 2402223197 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

FORMULA

a(n) is asymptotic to c*2^n where c=1.1186567921399193608303756752855835542518061417771006467002421299046146... [From Benoit Cloitre (benoit7848c(AT)orange.fr), Nov 10 2009]

MATHEMATICA

f[l_List] := Block[{n = Length[l] + 1}, Append[l, Sum[l[[k]]*Floor[n/k], {k, n - 1}]]]; Nest[f, {1}, 32] (*Chandler*)

CROSSREFS

Sequence in context: A072921 A087250 A065301 * A026522 A193044 A122491

Adjacent sequences:  A126653 A126654 A126655 * A126657 A126658 A126659

KEYWORD

nonn

AUTHOR

Leroy Quet Feb 09 2007

EXTENSIONS

Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Feb 11 2007

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Last modified February 14 05:53 EST 2012. Contains 205570 sequences.