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A131387
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Product of the nonzero digital products of n for all the bases 1 to n (a 'total digital-product factorial').
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5
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1, 1, 1, 1, 2, 4, 12, 48, 48, 192, 2880, 2880, 25920, 552960, 3265920, 1935360, 116121600, 278691840, 9405849600, 26754416640, 94058496000, 3210529996800, 869100503040000, 423789959577600, 927040536576000, 135612787064832000
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OFFSET
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1,5
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LINKS
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FORMULA
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a(n)=product{1<=p<=n, dp_p(n)} where dp_p(n) = product of the nonzero digits of n in base p.
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PROG
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(PARI) a(n) = {p = 1; for (b=2, n, digs = digits(n, b); p *= prod(k=1, #digs, if (digs[k], digs[k], 1)); ); return (p); } \\ Michel Marcus, Jul 15 2013
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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