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A090813 a(n)=3*(3^prime(n)-1)*B(2*prime(n)) where prime(n)=n-th prime and B(k) denotes the k-th Bernoulli number. 0
55, 7651, 3290729563, 6818200140583, 166441513807473717727, 1702709510836284027532747, 597359613401618666812910561358019, 49136798858325589887577115786547403314116681479 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,1

COMMENTS

Appears to be an integer value for n=3 up to 250.

LINKS

Table of n, a(n) for n=3..10.

PROG

(PARI) a(n)=3*(3^prime(n)-1)*bernfrac(2*prime(n))

CROSSREFS

Sequence in context: A028471 A004708 A269500 * A145617 A105842 A113632

Adjacent sequences:  A090810 A090811 A090812 * A090814 A090815 A090816

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Feb 11 2004

STATUS

approved

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Last modified December 13 22:07 EST 2018. Contains 318087 sequences. (Running on oeis4.)