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A032265 Number of ways to partition n labeled elements into pie slices of at least 2 elements allowing the pie to be turned over. 2
1, 0, 1, 1, 4, 11, 41, 162, 925, 5945, 47017, 402788, 3895937, 40556595, 461544253, 5625446270, 73716523405, 1028179882589, 15257484239777, 239529471989352, 3971376169852777, 69288230115817655, 1269563315949912469, 24366794306903776610, 488969030312192567573 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Andrew Howroyd, Table of n, a(n) for n = 0..200

C. G. Bower, Transforms (2)

FORMULA

"DIJ" (bracelet, indistinct, labeled) transform of 0, 1, 1, 1, ...

E.g.f.: 1 + (g(x) + g(x)^2/2 - log(1-g(x)))/2 where g(x) = exp(x) - x - 1. - Andrew Howroyd, Sep 12 2018

PROG

(PARI) seq(n)={my(p=exp(x + O(x*x^n))-x-1); Vec(1 + serlaplace(p + p^2/2 - log(1-p))/2)} \\ Andrew Howroyd, Sep 12 2018

CROSSREFS

Sequence in context: A214239 A278989 A000296 * A320155 A260320 A151273

Adjacent sequences:  A032262 A032263 A032264 * A032266 A032267 A032268

KEYWORD

nonn

AUTHOR

Christian G. Bower

EXTENSIONS

a(0)=1 prepended and terms a(22) and beyond from Andrew Howroyd, Sep 12 2018

STATUS

approved

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Last modified October 22 04:29 EDT 2018. Contains 316431 sequences. (Running on oeis4.)