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A059383
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Product J_4(i), i=1..n (cf. A059377).
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4
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1, 15, 1200, 288000, 179712000, 215654400000, 517570560000000, 1987470950400000000, 12878811758592000000000, 120545678060421120000000000, 1764788726804565196800000000000, 33883943554647651778560000000000000, 967725427920736934795673600000000000000
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| a(n) is also the determinant of the symmetric n X n matrix M defined by M(i,j) = gcd(i,j)^4 for 1 <= i,j <= n - Avi Peretz (njk(AT)netvision.net.il), Mar 22 2001
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REFERENCES
| L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 203, #17.
Antal Bege, Hadamard product of GCD matrices, Acta Univ. Sapientiae, Mathematica, 1, 1 (2009) 43-49
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LINKS
| Eric Weisstein's World of Mathematics, Le Paige's Theorem
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MATHEMATICA
| JordanTotient[n_, k_:1]:=DivisorSum[n, #^k*MoebiusMu[n/#]&]/; (n>0)&&IntegerQ[n]; A059383[n_]:=Times@@(JordanTotient[#, 4]&/@Range[n]); (* From Enrique Pérez Herrero, Aug 12 2011 *)
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CROSSREFS
| Cf. A001088.
Cf. A175836, A059381, A059382, A059383, A059384
Sequence in context: A090213 A027492 A001728 * A206394 A098723 A120296
Adjacent sequences: A059380 A059381 A059382 * A059384 A059385 A059386
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KEYWORD
| nonn
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com), Jan 28 2001
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