A067028 Numbers with a composite number of prime factors (counted with multiplicity).

16, 24, 36, 40, 54, 56, 60, 64, 81, 84, 88, 90, 96, 100, 104, 126, 132, 135, 136, 140, 144, 150, 152, 156, 160, 184, 189, 196, 198, 204, 210, 216, 220, 224, 225, 228, 232, 234, 240, 248, 250, 256, 260, 276, 294, 296, 297, 306, 308, 315, 324, 328, 330, 336

Offset

1,1

Links

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

Example

a(1)=16, 16 has 4 prime factors (counted with multiplicity) and 4 is composite.

Prog

(PARI) n=0; for (m=1, 10^10, if (!isprime(b=bigomega(m)) && b > 1, write("b067028.txt", n++, " ", m); if (n==1000, return))) \\ Harry J. Smith, Apr 26 2010
(PARI) is(n)=my(t=bigomega(n)); t>1 && !isprime(t) \\ Charles R Greathouse IV, Oct 15 2015

Crossrefs

Cf. A063989.

Sequence in context: A100316 A206260 A036328 * A110893 A014613 A323350

Adjacent sequences: A067025 A067026 A067027 * A067029 A067030 A067031

Keyword

nonn

Author

Shyam Sunder Gupta, Feb 16 2002

Status

approved