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A032221 Number of ways to partition n labeled elements into pie slices of different sizes of at least 2, allowing the pie to be turned over. 1

%I #12 Sep 11 2018 21:27:24

%S 1,0,1,1,1,11,16,57,85,1507,2896,12563,51074,138789,7999447,20571904,

%T 108097917,509724227,3208109968,10079065623,1222567789870,

%U 3713826929467,23585723568309,124658237924300,835203476167702,6007218866597341,26107540823949781

%N Number of ways to partition n labeled elements into pie slices of different sizes of at least 2, allowing the pie to be turned over.

%H Andrew Howroyd, <a href="/A032221/b032221.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 0, 1, 1, 1...

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

%K nonn

%O 0,6

%A _Christian G. Bower_

%E a(0)=1 prepended and terms a(24) and beyond from _Andrew Howroyd_, Sep 11 2018

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Last modified April 24 20:08 EDT 2024. Contains 371963 sequences. (Running on oeis4.)