OFFSET
1,4
COMMENTS
a(n) = 1 iff n is prime.
A068993(a(n)) = 4. - Reinhard Zumkeller, Mar 13 2011
Positions of first appearances are A328964. - Gus Wiseman, Nov 05 2019
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
MATHEMATICA
Table[PrimeNu[n]*PrimeOmega[n], {n, 1, 50}] (* G. C. Greubel, Apr 23 2017 *)
PROG
(PARI) list(n) = { local(x); for(x=1, n, print1(omega(x)*bigomega(x)", ") ) }
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Jan 29 2006
STATUS
approved