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A094661 Numerator of the sum of the ratios of consecutive primes. 2
3, 19, 137, 1289, 16909, 259087, 4975049, 106267661, 2725447213, 85953848147, 2903947942067, 115669053951809, 5061522951820999, 231945249314081827, 11594813068340357459, 650803589794759938517, 40385350464999429101033 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Table of n, a(n) for n=2..18.

FORMULA

a(n) = numerator(sum_{k=1..n} prime(k+1)/prime(k)).

MATHEMATICA

s=0; lst={}; Do[p=Prime[n]; r=Prime[n+1]; AppendTo[lst, Numerator[s+=r/p]], {n, 3*4!}]; lst (* Vladimir Joseph Stephan Orlovsky, Oct 24 2009 *)

PROG

(PARI) consec(n) = { y=0; forprime(x=2, n, y+=nextprime(x+1)/x; z=numerator(y); print1(z", ") ) }

CROSSREFS

Sequence in context: A221297 A138513 A321515 * A094662 A321349 A115750

Adjacent sequences:  A094658 A094659 A094660 * A094662 A094663 A094664

KEYWORD

nonn,frac

AUTHOR

Cino Hilliard, Jun 06 2004

STATUS

approved

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Last modified December 1 11:30 EST 2021. Contains 349429 sequences. (Running on oeis4.)