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A032155
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Number of ways to partition n elements into pie slices of different sizes other than one.
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1
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1, 0, 1, 1, 1, 2, 2, 3, 3, 6, 6, 9, 11, 14, 22, 27, 35, 46, 62, 73, 119, 138, 190, 239, 323, 402, 522, 753, 927, 1218, 1574, 2039, 2599, 3390, 4154, 6013, 7247, 9574, 12026, 15807, 19615, 25598, 31850, 40293, 54795, 67530, 86202, 109851
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OFFSET
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0,6
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LINKS
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FORMULA
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"CGK" (necklace, element, unlabeled) transform of 0, 1, 1, 1, ...
G.f.: 1 + Sum_{k>=1} (k-1)! * x^((k^2+3*k)/2) / (Product_{j=1..k} 1-x^j). - Andrew Howroyd, Sep 13 2018
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PROG
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(PARI) seq(n)=[subst(serlaplace(p/y*y^0), y, 1) | p <- Vec(y-1+prod(k=2, n, 1 + x^k*y + O(x*x^n)))] \\ Andrew Howroyd, Sep 13 2018
(PARI) seq(n)={Vec(1 + sum(k=1, n, my(r=(k^2+3*k)/2); if(r<=n, (k-1)! * x^r / prod(j=1, k, 1 - x^j + O(x*x^(n-r))))))} \\ Andrew Howroyd, Sep 13 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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