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A102845 Number of prime factors of the sum of the first n odd primes. 1
1, 3, 2, 2, 2, 4, 3, 3, 1, 2, 3, 3, 3, 2, 1, 3, 1, 2, 3, 3, 2, 4, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 4, 3, 3, 2, 4, 7, 2, 8, 3, 5, 2, 4, 4, 3, 2, 3, 4, 4, 2, 4, 1, 9, 1, 4, 3, 6, 2, 6, 1, 6, 2, 5, 1, 4, 2, 5, 3, 3, 1, 4, 3, 5, 1, 6, 2, 3, 2, 4, 3, 4, 3, 2, 2, 5, 2, 7, 2, 4, 2, 8, 3, 4, 1, 2, 4, 4, 2, 5, 4, 2, 4, 2, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Prime factors counted with multiplicity. - Harvey P. Dale, Sep 13 2016

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

a(2)=3 because 3+5=8=2*2*2;

a(3)=2 because 3+5+7=15=3*5.

MATHEMATICA

PrimeOmega[Accumulate[Prime[Range[2, 110]]]] (* Harvey P. Dale, Sep 13 2016 *)

PROG

(PARI) for(n=1, 105, print1(bigomega(sum(k=1, n, prime(k+1))), ", ")) (Shepherd)

CROSSREFS

Sequence in context: A104890 A064123 A024703 * A064126 A175333 A130845

Adjacent sequences:  A102842 A102843 A102844 * A102846 A102847 A102848

KEYWORD

easy,nonn

AUTHOR

Giovanni Teofilatto, Feb 28 2005

EXTENSIONS

More terms from Rick L. Shepherd, May 18 2005

STATUS

approved

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Last modified August 13 19:30 EDT 2020. Contains 336451 sequences. (Running on oeis4.)