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A032220 Number of ways to partition n labeled elements into pie slices of different odd sizes, allowing the pie to be turned over. 3
1, 1, 0, 1, 4, 1, 6, 1, 64, 505, 130, 1321, 1024, 13157, 2380, 395851, 17313664, 1639617, 73554666, 16100905, 919339264, 292018525, 18910614580, 1549052715, 1523900106304, 141366386526801, 9494469178116 (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

"DGJ" (bracelet, element, labeled) transform of 1, 0, 1, 0... (odds).

PROG

(PARI) seq(n)=[subst(serlaplace(p/y + polcoeff(p, 1) + polcoeff(p, 2)), y, 1)/2 | p <- Vec(serlaplace(y-1+prod(k=1, ceil(n/2), 1 + x^(2*k-1)*y/(2*k-1)! + O(x*x^n))))] \\ Andrew Howroyd, Sep 11 2018

CROSSREFS

Sequence in context: A087652 A072195 A032310 * A032145 A032050 A057160

Adjacent sequences:  A032217 A032218 A032219 * A032221 A032222 A032223

KEYWORD

nonn

AUTHOR

Christian G. Bower

EXTENSIONS

a(0)=1 prepended by Andrew Howroyd, Sep 11 2018

STATUS

approved

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Last modified October 23 06:29 EDT 2018. Contains 316520 sequences. (Running on oeis4.)