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A102068
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P(n)!, where P(n) is the largest prime factor of n (with a(1) = 1).
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4
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1, 2, 6, 2, 120, 6, 5040, 2, 6, 120, 39916800, 6, 6227020800, 5040, 120, 2, 355687428096000, 6, 121645100408832000, 120, 5040, 39916800, 25852016738884976640000, 6, 120, 6227020800, 6, 5040
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OFFSET
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1,2
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COMMENTS
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P(n)! is a multiple of n, for almost all n. The exceptions are A057109.
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REFERENCES
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I. Kastanas, The smallest factorial that is a multiple of n, Amer. Math. Monthly 101 (1994) 179.
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LINKS
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Table of n, a(n) for n=1..28.
A. Ivic, On a problem of Erdos involving the largest prime factor of n
Eric Weisstein's World of Mathematics, GreatestPrimeFactor
Index entries for sequences related to factorial numbers.
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FORMULA
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a(n) = A000142(A006530(n)) = A000040(A061395(n))!.
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EXAMPLE
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P(12)! = 3! = 6.
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CROSSREFS
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Cf. A000040, A000142, A006530, A057109, A061395, A102067.
Sequence in context: A122018 A005729 A086660 * A188733 A104290 A152549
Adjacent sequences: A102065 A102066 A102067 * A102069 A102070 A102071
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KEYWORD
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nonn
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AUTHOR
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Jonathan Sondow, Dec 28 2004
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STATUS
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approved
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