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A067655 Denominators of the coefficients in exp(2x/(1-x)) power series. 3
1, 1, 3, 3, 15, 45, 315, 315, 2835, 14175, 155925, 467775, 6081075, 3869775, 638512875, 638512875, 10854718875, 8881133625, 1856156927625, 9280784638125, 194896477400625, 2143861251406875, 2595200462229375 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

COMMENTS

Differs from A049606 at positions enumerated by A097324.

REFERENCES

K. Knopp "Theory and application of infinite series" Dover p. 547

O. Perron "Uber das infinitare Verhalten der koeffizienten einer gewissen Potenzreihe", Archiv d. math.u.Phys.(3), Vol. 22, pp. 329-340. 1914

FORMULA

a(n) is the denominator in sum(i=1, n, C(n-1, i-1)*2^i/i!)

CROSSREFS

Cf. A067654.

Sequence in context: A078631 A160639 A046983 * A160624 A049606 A046126

Adjacent sequences:  A067652 A067653 A067654 * A067656 A067657 A067658

KEYWORD

nonn,frac

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Feb 03 2002

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.