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A064028
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Sum of unitary divisors of n!.
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0
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1, 3, 12, 36, 216, 1020, 8160, 61920, 507744, 4383392, 52600704, 624249600, 8739494400, 109190390400, 1583122968000, 25318378008000, 455730804144000
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OFFSET
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1,2
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LINKS
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Table of n, a(n) for n=1..17.
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FORMULA
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a(n)=usigma(n!)=A034448[A000142(n)]
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EXAMPLE
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n=6,6!=720, sum of the 8 unitary one of its 30 divisors is 1020, a(6)=720+1+16+45+9+80+5+144=1020
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CROSSREFS
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Cf. A034448, A003444, A046656, A056657, A056171, A056172, A000203, A000142, A062569.
Sequence in context: A155714 A004661 A074430 * A110950 A102744 A145951
Adjacent sequences: A064025 A064026 A064027 * A064029 A064030 A064031
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KEYWORD
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nonn
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AUTHOR
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Labos E. (labos(AT)ana.sote.hu), Sep 11 2001
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STATUS
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approved
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