login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 3 09:50 EST 2022. Contains 358517 sequences. (Running on oeis4.)