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A067911
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Product of gcd(k,n) for 1 <= k <= n.
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9
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1, 2, 3, 8, 5, 72, 7, 128, 81, 800, 11, 41472, 13, 6272, 30375, 32768, 17, 3359232, 19, 20480000, 750141, 247808, 23, 13759414272, 15625, 1384448, 1594323, 5035261952, 29, 30233088000000, 31, 2147483648, 235782657, 37879808
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OFFSET
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1,2
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LINKS
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FORMULA
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MAPLE
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with(numtheory): a := n -> mul(d^phi(n/d), d = divisors(n)):
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MATHEMATICA
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a[n_] := Product[d^EulerPhi[n/d], {d, Divisors[n]}];
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PROG
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(Sage)
A067911 = lambda n: mul(gcd(n, i) for i in range(n))
(PARI) a(n) = prod(k=1, n, gcd(k, n)); \\ Michel Marcus, Aug 23 2016
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CROSSREFS
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In A018804 the product is replaced by sum.
Product of terms in n-th row of A050873.
Cf. A000010 (comments on product formulas).
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KEYWORD
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nonn
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AUTHOR
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Sharon Sela (sharonsela(AT)hotmail.com), Mar 10 2002
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EXTENSIONS
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STATUS
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approved
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