The On-Line Encyclopedia of Integer Sequences (OEIS)

A090645 revision #6

A090645

a(n)=(-1)^(n+1)*2*(16^n-1)*B(2n) where B(k) denotes the k-th Bernoulli number.

0, 5, 17, 195, 4369, 158875, 8493081, 626349395, 60921163553, 7555181167755, 1163556514166185, 217865966280741955, 48740349457479955377, 12839917161220487631995, 3934089704476487908489529

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OFFSET

0,2

LINKS

Table of n, a(n) for n=0..14.

MATHEMATICA

Table[(-1)^(n+1) 2(16^n-1)BernoulliB[2n], {n, 0, 20}] (* From Harvey P. Dale, Nov 10 2011 *)

PROG

(PARI) a(n)=(-1)^(n+1)*2*(16^n-1)*bernfrac(2*n)

CROSSREFS

Sequence in context: A309178 A164740 A053678 * A206328 A096407 A216428

Adjacent sequences: A090642 A090643 A090644 * A090646 A090647 A090648

KEYWORD

nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Dec 13 2003

STATUS

approved