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A144489 Partial sums of A087624. 1
0, 0, 0, 1, 1, 3, 3, 4, 5, 7, 7, 9, 9, 11, 13, 14, 14, 16, 16, 18, 20, 22, 22, 24, 25, 27, 28, 30, 30, 33, 33, 34, 36, 38, 40, 42, 42, 44, 46, 48, 48, 51, 51, 53, 55, 57, 57, 59, 60, 62, 64, 66, 66, 68, 70, 72, 74, 76, 76, 79, 79, 81, 83, 84, 86, 89, 89, 91, 93, 96, 96, 98, 98, 100, 102 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,6
COMMENTS
Number of pairs (p,q) with 1 < p < q <= n, p|q and p prime. - Wesley Ivan Hurt, Oct 30 2022
LINKS
MATHEMATICA
Accumulate[Array[If[PrimeQ[#], 0, PrimeNu[#]]&, 110]] (* Harvey P. Dale, Jul 19 2019 *)
PROG
(PARI) a(n) = sum(k=1, n, if (!isprime(k), omega(k))); \\ Michel Marcus, Nov 06 2022
CROSSREFS
Sequence in context: A104804 A240207 A347286 * A239640 A100091 A239483
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Dec 11 2008
STATUS
approved

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Last modified April 19 23:40 EDT 2024. Contains 371798 sequences. (Running on oeis4.)