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A164020 Denominators of Bernoulli numbers interleaved with even numbers. 7
1, 2, 6, 4, 30, 6, 42, 8, 30, 10, 66, 12, 2730, 14, 6, 16, 510, 18, 798, 20, 330, 22, 138, 24, 2730, 26, 6, 28, 870, 30, 14322, 32, 510, 34, 6, 36, 1919190, 38, 6, 40, 13530, 42, 1806, 44, 690, 46, 282, 48, 46410, 50, 66, 52, 1590, 54, 798, 56, 870, 58, 354, 60, 56786730 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..1000

Eric Weisstein's World of Mathematics, Bernoulli Number

FORMULA

a(2*n) = A002445(n).

a(2*n+1) = 2*(n+1).

a(n) divides A057643(n). Franklin T. Adams-Watters, Aug 03 2012

MATHEMATICA

a[n_]:=If[OddQ[n], n+1, BernoulliB[n] // Denominator]; Table[a[n], {n, 0, 60}](* Jean-François Alcover, Dec 29 2012 *)

With[{nn=60}, Riffle[Denominator[BernoulliB[Range[0, nn, 2]]], Range[2, nn, 2]]] (* Harvey P. Dale, Jul 18 2015 *)

PROG

(MAGMA) [IsEven(n) select Denominator(Bernoulli(n)) else n+1: n in [0..100]]; // Vincenzo Librandi, Sep 08 2017

CROSSREFS

Cf. A027642, A141056, A160014.

Sequence in context: A263326 A226532 A006233 * A057643 A073039 A322792

Adjacent sequences:  A164017 A164018 A164019 * A164021 A164022 A164023

KEYWORD

nonn

AUTHOR

Paul Curtz, Aug 08 2009

EXTENSIONS

Extended by R. J. Mathar, Sep 23 2009

STATUS

approved

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Last modified April 23 18:06 EDT 2019. Contains 322387 sequences. (Running on oeis4.)