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A123536 a(n)=(-1)^(n+1)*B(2n)*prod(p<=2n+1,p) where B(2n) denotes the (2n)-th Bernoulli number and p is prime. 0
1, 1, 1, 5, 7, 175, 7601, 35035, 3620617, 533203385, 5132341123, 1381418533495, 19315437152429, 318022715945935, 176611180730425441, 120653354922346558325, 3031735699207849905271, 86163723379372590236285 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Table of n, a(n) for n=0..17.

PROG

(PARI) a(n)=(-1)^(n+1)*bernfrac(2*n)*prod(p=1, 2*n+1, if(isprime(p), p, 1))

CROSSREFS

Cf. A002445.

Sequence in context: A158969 A083842 A164372 * A057177 A211769 A229030

Adjacent sequences:  A123533 A123534 A123535 * A123537 A123538 A123539

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Nov 11 2006

STATUS

approved

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Last modified July 29 17:12 EDT 2014. Contains 245040 sequences.