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A326580
a(n) = (2*n+1)*denominator((2*n+1)*Bernoulli(2*n)).
1
1, 6, 30, 42, 90, 66, 2730, 30, 510, 798, 2310, 138, 13650, 54, 870, 14322, 5610, 210, 1919190, 78, 13530, 1806, 2070, 282, 324870, 1122, 1590, 43890, 16530, 354, 56786730, 126, 6630, 64722, 690, 4686, 140100870, 150, 2310, 3318, 6210270, 498, 57873270, 174
OFFSET
0,2
LINKS
FORMULA
a(n) = A326579(2*n + 1).
MAPLE
A326580 := n -> (2*n+1)*denom((2*n+1)*bernoulli(2*n)):
seq(A326580(n), n=0..43);
MATHEMATICA
Table[(2n+1)Denominator[(2n+1)BernoulliB[2n]], {n, 0, 50}] (* Harvey P. Dale, Jul 31 2021 *)
PROG
(PARI) a(n) = (2*n+1)*denominator((2*n+1)*bernfrac(2*n)); \\ Michel Marcus, Jul 19 2019
CROSSREFS
Cf. A326579, A326578, A326478, A027641/A027642 (Bernoulli).
Sequence in context: A114649 A090126 A291566 * A070195 A241190 A276933
KEYWORD
nonn
AUTHOR
Peter Luschny, Jul 17 2019
STATUS
approved