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A036283 Write cosec x = 1/x + Sum e_n x^(2n-1)/(2n-1)!; sequence gives denominators of e_n. 11
6, 60, 126, 120, 66, 16380, 6, 4080, 7182, 3300, 138, 32760, 6, 1740, 42966, 8160, 6, 34545420, 6, 270600, 37926, 1380, 282, 1113840, 66, 3180, 21546, 3480, 354, 1703601900, 6, 16320, 194166, 60, 4686, 5043631320, 6, 60, 9954, 9200400, 498, 142981020, 6 (list; graph; refs; listen; history; text; internal format)
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).

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

CROSSREFS

Cf. A036280-A036282.

Cf. A000292, A006953, A107963, A160487, A161739, A161740, A161741.

Sequence in context: A324199 A137498 A250070 * A228838 A225945 A126576

Adjacent sequences:  A036280 A036281 A036282 * A036284 A036285 A036286

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

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

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Last modified November 14 17:24 EST 2019. Contains 329126 sequences. (Running on oeis4.)