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

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A074594 Number of distinct prime factors of numbers that are not prime powers. 4
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 3, 2, 2, 2, 2, 2, 3, 2, 2, 3, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 3, 2, 2, 3, 2, 2, 3, 2, 2, 2, 2, 2, 3, 2, 2, 2, 3, 2, 3, 3, 2, 2, 2, 2, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 3, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
a(n) = A001221(A024619(n)).
MATHEMATICA
PrimeNu/@Select[Range[2, 300], !PrimePowerQ[#]&] (* Harvey P. Dale, Nov 18 2018 *)
CROSSREFS
Sequence in context: A090620 A151659 A057467 * A211667 A001069 A156877
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Aug 25 2002
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 February 28 09:39 EST 2024. Contains 370394 sequences. (Running on oeis4.)