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A091852
Numerator of Sum_{i=1..n} prime(i)/prime(i+1).
3
2, 19, 208, 3023, 52004, 1079263, 24845332, 663589691, 21809669044, 769910292199, 31595368408378, 1432693760237483, 67842962092519574, 3469898586979325623, 198354535000733806154, 12566530264688830748431
OFFSET
1,1
COMMENTS
Proposed by Mohammed BOUAYOUN, Feb 16 2004; computed by R. K. Guy, Feb 17 2004
EXAMPLE
The sums are f(1)=2/3, f(2)=2/3 + 3/5, f(3)=2/3+3/5+5/7, f(4)=2/3+3/5+5/7+7/11, ...
MATHEMATICA
A091852[n_] := Numerator[ Sum[ Prime[i] / Prime[i + 1], {i, n}]]; Table[ A091852[n], {n, 16}] (* Robert G. Wilson v, Mar 16 2004 *)
CROSSREFS
Denominators are in A070826.
Sequence in context: A037071 A126039 A349256 * A210986 A232525 A024227
KEYWORD
nonn,frac
AUTHOR
N. J. A. Sloane, Mar 13 2004
EXTENSIONS
More terms from Robert G. Wilson v, Mar 16 2004
STATUS
approved