A063745 Even numbers with an even number of prime factors (counted with multiplicity).

4, 6, 10, 14, 16, 22, 24, 26, 34, 36, 38, 40, 46, 54, 56, 58, 60, 62, 64, 74, 82, 84, 86, 88, 90, 94, 96, 100, 104, 106, 118, 122, 126, 132, 134, 136, 140, 142, 144, 146, 150, 152, 156, 158, 160, 166, 178, 184, 194, 196, 198, 202, 204, 206, 210, 214, 216, 218, 220

Offset: 1

Author

Shyam Sunder Gupta, Feb 16 2002

Keywords

• nonn

Examples

			a(2)=6, which is even with even number of prime factors, i.e., 2.
		

Links

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

Crossrefs

Intersection of A028260 and A005843.

Cf. A046337.

Programs

Mathematica

Select[2*Range[200],EvenQ[PrimeOmega[#]]&] (* Harvey P. Dale, Mar 07 2015 *)

PARI

isok(k) = { k%2==0 && bigomega(k)%2 == 0 } \\ Harry J. Smith, Aug 29 2009