OFFSET
1,1
COMMENTS
Denominator of [2^(2n-1) - 1] * Bernoulli(2n)/n.
Equals the denominators of the LS1[-2*m,n=1] matrix coefficients of A160487 for m = 1, 2, ... - Johannes W. Meijer, May 24 2009
The products of the first n terms of this sequence appear in the denominators of the a(n) formulas of the right hand columns of triangle A161739. See A000292 (n=1), A107963 (n=2), A161740 (n=3) and A161741 (n=4). The next six values of n show that this pattern persists. - Johannes W. Meijer, Oct 22 2009
REFERENCES
M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, Tenth Printing, 1972, p. 75 (4.3.68).
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].
M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, Tenth Printing, 1972, p. 75 (4.3.68).
FORMULA
Apparently a(n) = 6*A202318(n). - Hugo Pfoertner, Dec 18 2022
EXAMPLE
x^(-1)+1/6*x+7/360*x^3+31/15120*x^5+...
MAPLE
seq(denom((2^(2*n-1)-1)*bernoulli(2*n)/n), n=1..100); # Robert Israel, Oct 14 2016
PROG
(PARI) a(n) = denominator((2^(2*n-1)-1)*bernfrac(2*n)/n) \\ Hugo Pfoertner, Dec 18 2022
CROSSREFS
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
Title corrected and offset changed by Johannes W. Meijer, May 21 2009
More terms, and edited by Robert Israel, Oct 14 2016
STATUS
approved