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A083688 Denominator of B(2n)*H(2n)/n*(-1)^(n+1) where B(k) is the k-th Bernoulli number and H(k) the k-th harmonic number. 1
4, 144, 360, 33600, 15120, 34927200, 2162160, 172972800, 1543782240, 10242872640, 10346336, 2338727174784, 53542288800, 4818805992000, 3228118134040800, 1178332991611776000, 78765574305600 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

LINKS

Ira Gessel, On Miki's identy for Bernoulli numbers J. Number Theory 110 (2005), no. 1, 75-82.

FORMULA

Miki's identity : B(n)*H(n)*(2/n) = sum(i=2, n-2, B(i)/i*B(n-i)/(n-i)*(1-C(n, i)))

PROG

(PARI) a(n)=denominator((-1)^(n+1)*bernfrac(2*n)*sum(k=1, 2*n, 1/k)/n)

CROSSREFS

Cf. A083687.

Sequence in context: A119038 A048432 A122422 * A053899 A058414 A053891

Adjacent sequences:  A083685 A083686 A083687 * A083689 A083690 A083691

KEYWORD

frac,nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 15 2003

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Last modified February 14 23:53 EST 2012. Contains 205689 sequences.