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A032220
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Number of ways to partition n labeled elements into pie slices of different odd sizes, allowing the pie to be turned over.
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3
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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
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OFFSET
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0,5
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LINKS
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FORMULA
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"DGJ" (bracelet, element, labeled) transform of 1, 0, 1, 0... (odds).
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PROG
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(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
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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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