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A214391 Denominators of Sum_{n>=1} 1/A045542(n). 6
3, 21, 168, 280, 210, 1365, 42315, 8463, 45136, 406224, 253890, 310310, 744744, 744744, 94582488, 661416, 110236, 21496020, 924328860, 7394630880, 894750336480, 5070251906720, 5704033395060, 6375096147420, 6375096147420, 2550038458968, 2550038458968 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Goldbach-Euler: sum A214390(n)/a(n) -> 1, n -> oo.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

L. Bibiloni, P. Viader, and J. Paradis, On a Series of Goldbach and Euler, Amer. Math. Monthly, 113 (2006), pp. 206-220.

PROG

(Haskell)

import Data.Ratio ((%), denominator)

a214391 n = a214391_list !! (n-1)

a214391_list = map denominator $ scanl1 (+) $ map (1 %) a045542_list

CROSSREFS

Cf. A214390 (numerators).

Sequence in context: A179815 A118353 A262977 * A046637 A220103 A132805

Adjacent sequences:  A214388 A214389 A214390 * A214392 A214393 A214394

KEYWORD

nonn,frac

AUTHOR

Reinhard Zumkeller, Jul 15 2012

STATUS

approved

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Last modified September 17 04:03 EDT 2019. Contains 327119 sequences. (Running on oeis4.)