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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

%I

%S 1,1,0,1,4,1,6,1,64,505,130,1321,1024,13157,2380,395851,17313664,

%T 1639617,73554666,16100905,919339264,292018525,18910614580,1549052715,

%U 1523900106304,141366386526801,9494469178116

%N Number of ways to partition n labeled elements into pie slices of different odd sizes, allowing the pie to be turned over.

%H Andrew Howroyd, <a href="/A032220/b032220.txt">Table of n, a(n) for n = 0..200</a>

%H C. G. Bower, <a href="/transforms2.html">Transforms (2)</a>

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

%o (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

%K nonn

%O 0,5

%A _Christian G. Bower_

%E a(0)=1 prepended by _Andrew Howroyd_, Sep 11 2018

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Last modified February 7 16:06 EST 2023. Contains 360128 sequences. (Running on oeis4.)