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A059384
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a(n) = Product_{i=1..n} J_5(i).
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6
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1, 31, 7502, 7441984, 23248758016, 174412182636032, 2931171141381153792, 93047096712003345973248, 5471727569246068763302821888, 529903984716066283313298482921472, 85341036738522474927606720674503065600, 20487310643596659421020979792003903940198400
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OFFSET
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1,2
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COMMENTS
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a(n) is also the determinant of the symmetric n X n matrix M defined by M(i,j) = gcd(i,j)^5 for 1 <= i,j <= n. - Avi Peretz (njk(AT)netvision.net.il), Mar 22 2001
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REFERENCES
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L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 203, #17.
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LINKS
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MATHEMATICA
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JordanTotient[n_Integer, k_: 1] := DivisorSum[n, #^k*MoebiusMu[n/#] &]; f[n_] := Times @@ (JordanTotient[#, 5] & /@ Range[n]); (* Enrique Pérez Herrero *) Array[f, 11] (* Robert G. Wilson v, Oct 08 2011 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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