

A063989


Numbers with a prime number of prime divisors (counted with multiplicity).


13



4, 6, 8, 9, 10, 12, 14, 15, 18, 20, 21, 22, 25, 26, 27, 28, 30, 32, 33, 34, 35, 38, 39, 42, 44, 45, 46, 48, 49, 50, 51, 52, 55, 57, 58, 62, 63, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 82, 85, 86, 87, 91, 92, 93, 94, 95, 98, 99, 102, 105, 106
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OFFSET

1,1


LINKS

Harry J. Smith, Table of n, a(n) for n = 1..1000


MAPLE

with(numtheory); a := []: for i from 1 to 300 do if isprime(bigomega(i)) then a := [op(a), i]; fi; od: a;


MATHEMATICA

Select[Range[200], PrimeQ[PrimeOmega[#]]&] (* Harvey P. Dale, Jul 25 2015 *)


PROG

(PARI) n=0; for (m=1, 10^9, if (isprime(bigomega(m)), write("b063989.txt", n++, " ", m); if (n==1000, break))) \\ Harry J. Smith, Sep 05 2009
(PARI) is(n)=isprime(bigomega(n)) \\ Charles R Greathouse IV, Sep 18 2015


CROSSREFS

Sequence in context: A341321 A063806 A323521 * A168645 A282668 A117097
Adjacent sequences: A063986 A063987 A063988 * A063990 A063991 A063992


KEYWORD

nonn


AUTHOR

N. J. A. Sloane, Sep 18 2001


STATUS

approved



