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A100513 Denominator of Sum_{k=0..n} 1/C(2n,2k). 5
1, 1, 6, 15, 35, 315, 13860, 3003, 9009, 765765, 1385670, 14549535, 66927861, 371821450, 40156716600, 145568097675, 136745788725, 128931743655, 9025222055850, 4281195077775, 166966608033225, 6845630929362225, 26165522663340060, 294362129962575675 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

REFERENCES

M. Klamkin, ed., Problems in Applied Mathematics: Selections from SIAM Review, SIAM, 1990; see pp. 126-127.

LINKS

Table of n, a(n) for n=0..23.

EXAMPLE

1, 2, 13/6, 32/15, 73/35, 647/315, 28211/13860, 6080/3003, 18181/9009, 1542158/765765, 2786599/1385670, 29229544/14549535, 134354573/66927861, ... = A100512/A100513.

CROSSREFS

Cf. A100512, A046825.

Sequence in context: A274320 A099620 A045969 * A191002 A127469 A103106

Adjacent sequences:  A100510 A100511 A100512 * A100514 A100515 A100516

KEYWORD

nonn,frac

AUTHOR

N. J. A. Sloane, Nov 25 2004

STATUS

approved

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Last modified September 28 13:24 EDT 2020. Contains 337393 sequences. (Running on oeis4.)