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A084086 Length of lists created by n substitutions k -> Range[ -1-Abs[k]+MoebiusMu[Abs[k]],k+1+MoebiusMu[Abs[k]],2] starting with {-1}. 0
1, 2, 5, 15, 44, 125, 347, 948, 2561, 6863, 18284, 48501, 128243, 338276, 890681, 2341959, 6151580, 16145549, 42350603, 111037332, 291023537, 762557567, 1997697740, 5232632805, 13704394979, 35888940740, 93979204457, 246082227063 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

equivalent to -10->{-10,-8}; -9->{-10,-8}; -8->{-9,-7}; -7->{-9,-7}; -5-> {-7,-5}; -3->{-5,-3}; -1->{-1,1}; 1->{-1,1,3}; 3->{-5,-3,-1,1,3}.

LINKS

Table of n, a(n) for n=0..27.

FORMULA

G.f.: -(1-3 x+2 x^2+2 x^3)/(-7 x^2-1+5 x+2 x^3)

EXAMPLE

length of {-1}, {-1,1}, {-1,1,-1,1,3}, {-1,1,-1,1,3,-1,1,-1,1,3,-5,-3,-1,1,3} is 1,2,5,15

MATHEMATICA

Length/@Flatten/@NestList[ # /. k_Integer:>Range[ -1-Abs[k]+MoebiusMu[Abs[k]], k+1+MoebiusMu[Abs[k]], 2]&, {-1}, 8]

CROSSREFS

Sequence in context: A304201 A215448 A094176 * A307259 A292524 A071742

Adjacent sequences:  A084083 A084084 A084085 * A084087 A084088 A084089

KEYWORD

nonn

AUTHOR

Wouter Meeussen, May 11 2003

STATUS

approved

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Last modified October 23 17:32 EDT 2019. Contains 328373 sequences. (Running on oeis4.)