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A046669

Partial sums of A020639.

1, 3, 6, 8, 13, 15, 22, 24, 27, 29, 40, 42, 55, 57, 60, 62, 79, 81, 100, 102, 105, 107, 130, 132, 137, 139, 142, 144, 173, 175, 206, 208, 211, 213, 218, 220, 257, 259, 262, 264, 305, 307, 350, 352, 355, 357, 404, 406, 413, 415, 418, 420, 473

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

REFERENCES

M. Kalecki, On certain sums extended over primes or prime factors (in Polish), Prace Mat., Vol. 8 (1963/64), pp. 121-129.

József Sándor, Dragoslav S. Mitrinovic and Borislav Crstici, Handbook of Number Theory I, Springer Science & Business Media, 2005, Section IV.1, p. 121.

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

A. E. Brouwer, Two number theoretic sums, Stichting Mathematisch Centrum. Zuivere Wiskunde, Report ZW 19/74 (1974): 3 pages. [Cached copy, included with the permission of the author]

FORMULA

a(n) = A088821(n) + 1.

From Amiram Eldar, Mar 04 2021: (Start)

a(n) ~ ((1 + o(1))/2)* n^2/log(n) (Kalecki, 1963/64).

a(n) = (1/2) * n^2/log(n) + O(n^2/log(n)^2) (Brouwer, 1974). (End)

MATHEMATICA

Accumulate[Array[FactorInteger[#][[1, 1]]&, 60]] (* Harvey P. Dale, Apr 20 2011 *)

PROG

(Haskell)

a046669 n = a046669_list !! (n-1)

A046669_list = scanl1 (+) a020639_list -- Reinhard Zumkeller, Jun 15 2013

CROSSREFS