A120832 Denominators of partial sums of (p+q)/p*q, where p and q are primes.

1, 6, 2, 5, 70, 210, 210, 1155, 1155, 30030, 10010, 85085, 17017, 646646, 1939938, 22309287, 22309287, 22309287, 111546435, 37182145, 2156564410, 33426748355, 33426748355, 100280245065, 7420738134810, 7420738134810

Offset: 1

Author

Reinhard Zumkeller, Jul 24 2006

Keywords

• nonn
• frac

Comments

Numerators: A120831(n);

A120831(n)/a(n) = Sum(A068318(n)/A001358(n):1<=k<=n).

Examples

			n=5: (2+2)/2*2+(2+3)/2*3+(3+3)/3*3+(2+5)/2*5+(2+7)/2*7 =
4/4 + 5/6 + 6/9 + 7/10 + 9/14 = 269/70 = A120831(5)/a(5).
		

Crossrefs

Cf. A120835, A120834.