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 A106458 Bernoulli number denominators, with zeros at the odd places. 3
 1, 2, 6, 0, 30, 0, 42, 0, 30, 0, 66, 0, 2730, 0, 6, 0, 510, 0, 798, 0, 330, 0, 138, 0, 2730, 0, 6, 0, 870, 0, 14322, 0, 510, 0, 6, 0, 1919190, 0, 6, 0, 13530, 0, 1806, 0, 690, 0, 282, 0, 46410, 0, 66, 0, 1590, 0, 798, 0, 870, 0, 354, 0, 56786730 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS A027642 is the correct version of this sequence. - N. J. A. Sloane. Equals right border of triangle A159688 if zeros are inserted in A159688 to allow for (n+1) terms per row. - Gary W. Adamson, Apr 19 2009 REFERENCES Robert M. Young, "Excursions in Calculus" MAA, 1992, p. 91 J. H. Conway & R. K. Guy, "The Book of Numbers", Springer-Verlag, 1996, p. 108 LINKS Antti Karttunen, Table of n, a(n) for n = 0..16384 FORMULA In addition to generating functions as shown in A006954, the Bernoulli numbers starting with B(1)= -1/2 may be generated from the following system of simultaneous equations: (exemplified by 5 rows): 2 0 0 0 0 = -1 3 3 0 0 0 = -1 4 6 4 0 0 = -1 5 10 10 5 0 = -1 6 15 20 15 6 = -1 EXAMPLE Solutions to the system of simultaneous equations with 5 rows: (-1/2, 1/6, 0, -1/30, 0) MATHEMATICA a[n_] := If[OddQ[n] && n>2, 0, BernoulliB[n] // Denominator]; Table[a[n], {n, 0, 60}] (* Jean-François Alcover, Dec 29 2012 *) PROG (PARI) A106458(n) = if((n%2)&&n>1, 0, denominator(bernfrac(n))); \\ Antti Karttunen, Dec 19 2018 CROSSREFS Cf. A027642, A006954, A007318. A159688 [From Gary W. Adamson, Apr 19 2009] Sequence in context: A285119 A202535 A138703 * A213323 A293016 A122685 Adjacent sequences:  A106455 A106456 A106457 * A106459 A106460 A106461 KEYWORD nonn,frac AUTHOR Gary W. Adamson, May 02 2005 EXTENSIONS Typo in one term corrected by Paul Curtz, Jul 16 2008 STATUS approved

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Last modified March 22 04:32 EDT 2019. Contains 321406 sequences. (Running on oeis4.)