A225904 Numerator of Sum_{k=1..n} 1/L(k) where L(n) is the n-th Lucas number (A000204).

1, 4, 19, 145, 1679, 5191, 153311, 7286005, 69689327, 2869226821, 572447760301, 6593608277800, 3438637721790797, 966842075996112436, 119933240206586434591, 264753799412041684949165, 945570749875765527295137611, 303554979754466691916744807193

Offset: 1

Author

Michel Lagneau, May 20 2013

Keywords

• nonn
• frac
• easy

Examples

			1, 4/3, 19/12, 145/84, 1679/924, 5191/2772, ... = A225904/A225905.
		

Crossrefs

Cf. A000204, A059248, A035105, A225905.

Programs

Mathematica

Numerator[Table[Sum[1/LucasL[k], {k, 1, n}], {n, 1, 30}]]
Numerator[Accumulate[1/LucasL[Range[20]]]] (* Harvey P. Dale, Sep 16 2016 *)