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A085288
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Number of sorted multiplicative partitions of n!.
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4
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1, 1, 3, 3, 10, 10, 30, 75, 220, 220, 588, 588, 1568, 3696, 11616, 11616, 30492, 30492, 84700, 173250, 441000, 441000, 1262520, 2777544, 6957720, 16731660, 43506760, 43506760, 98658000, 98658000, 277101000, 541886400, 1322481600, 2715495552
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OFFSET
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2,3
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COMMENTS
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Number of decompositions of n! into factors of the form (p_k)^(e^k).
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LINKS
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FORMULA
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EXAMPLE
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4! = 3*8 = 2*3*4 = 2*2*2*3, so a(4)=3.
5! = 3*5*8 = 2*3*4*5 = 2*2*2*3*5, so a(5)=3.
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MATHEMATICA
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f[n_] := Times @@ PartitionsP /@ Last /@ FactorInteger[ n!]; Array[f, 34, 2] (* Robert G. Wilson v, Sep 22 2006 *)
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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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