

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
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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", SpringerVerlag, 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}] (* JeanFrançois 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



