A214391 Denominators of Sum_{n>=1} 1/A045542(n).

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

Offset: 1

Author

Reinhard Zumkeller, Jul 15 2012

Keywords

• nonn
• frac

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.

Crossrefs

Cf. A214390 (numerators).

Programs

Haskell

import Data.Ratio ((%), denominator)
a214391 n = a214391_list !! (n-1)
a214391_list = map denominator $ scanl1 (+) $ map (1 %) a045542_list