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A102862 Numbers of prime factors of the sum of the first n primes. 1
1, 1, 2, 1, 3, 1, 2, 2, 4, 2, 6, 1, 3, 1, 4, 2, 5, 2, 4, 3, 4, 2, 3, 3, 4, 4, 5, 2, 5, 4, 5, 2, 4, 2, 3, 2, 5, 2, 3, 5, 3, 3, 3, 2, 4, 2, 3, 2, 5, 3, 4, 6, 4, 2, 2, 3, 4, 2, 2, 1, 3, 3, 3, 1, 2, 2, 3, 3, 3, 3, 5, 2, 3, 4, 2, 3, 4, 3, 6, 4, 3, 2, 6, 4, 5, 3, 5, 4, 4, 3, 5, 2, 2, 2, 6, 1, 4, 3, 5, 1, 5, 1, 7, 2, 5 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A001222(A007504(n)). - Amiram Eldar, Mar 09 2020

EXAMPLE

a(3) = 2 because 2+3+5 = 10 = 2*5.

a(5) = 3 because 2+3+5+7+11 = 28 = 2*2*7.

MATHEMATICA

PrimeOmega @ Accumulate @ Select[Range[230], PrimeQ] (* Amiram Eldar, Mar 09 2020 *)

PROG

(PARI) for(n=1, 105, print1(bigomega(sum(k=1, n, prime(k))), ", ")) \\ Rick L. Shepherd, May 17 2005

CROSSREFS

Cf. A001222, A007504.

Sequence in context: A339443 A342655 A161901 * A029331 A037269 A124579

Adjacent sequences:  A102859 A102860 A102861 * A102863 A102864 A102865

KEYWORD

nonn

AUTHOR

Giovanni Teofilatto, Mar 01 2005

EXTENSIONS

More terms from Rick L. Shepherd, May 17 2005

STATUS

approved

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Last modified May 12 10:17 EDT 2021. Contains 343821 sequences. (Running on oeis4.)