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A120272 Numerator of Sum_{k=1..n} k/prime(k). 1
0, 1, 7, 53, 491, 6451, 97723, 1871501, 39642599, 999076987, 31204161323, 1038495626543, 40831064063651, 1770543222362221, 80392862250956443, 3974705945770003271, 220497651647226035923, 13563377141298566879867, 861975691921988407175147, 59980850604601955729416979 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Harvey P. Dale, Table of n, a(n) for n = 0..349

FORMULA

a(n) = A258851(A002110(n)). - Alois P. Heinz, Jun 26 2015

MATHEMATICA

Numerator[Table[Sum[i/Prime[i], {i, 1, n}], {n, 1, 20}]]

Numerator[Accumulate[Table[n/Prime[n], {n, 20}]]] (* Harvey P. Dale, Jan 21 2013 *)

PROG

(PARI) for(n=0, 20, print1(if(n==0, 0, numerator(sum(k=1, n, k/prime(k)))), ", ")) \\ G. C. Greubel, Aug 23 2018

(MAGMA) [0] cat [Numerator((&+[k/NthPrime(k): k in [1..n]])): n in [1..20]]; // G. C. Greubel, Aug 23 2018

CROSSREFS

Denominators are in A002110.

Sequence in context: A163306 A081338 A142981 * A057180 A137612 A092802

Adjacent sequences:  A120269 A120270 A120271 * A120273 A120274 A120275

KEYWORD

frac,nonn

AUTHOR

Alexander Adamchuk, Jul 01 2006

EXTENSIONS

a(0)=0 prepended by Alois P. Heinz, Jun 26 2015

STATUS

approved

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Last modified October 19 05:24 EDT 2018. Contains 316336 sequences. (Running on oeis4.)