login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A120831
Numerators of partial sums of (p+q)/p*q, where p and q are primes.
4
1, 11, 5, 16, 269, 919, 1019, 6287, 6749, 192799, 68513, 629908, 131816, 5366365, 16894967, 206416733, 212790815, 221539555, 1140147647, 394400219, 24027859197, 390223473936, 399480111942, 1236227094836, 95391734575399
OFFSET
1,2
COMMENTS
Denominators: A120832(n);
a(n)/A120832(n) = Sum(A068318(n)/A001358(n):1<=k<=n).
EXAMPLE
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 = a(5)/A120832(5).
CROSSREFS
Sequence in context: A085716 A127820 A168206 * A253254 A373730 A363347
KEYWORD
nonn,frac
AUTHOR
Reinhard Zumkeller, Jul 24 2006
STATUS
approved