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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 August 3 12:33 EDT 2021. Contains 346438 sequences. (Running on oeis4.)