OFFSET
1,1
COMMENTS
Also, numbers expressible as the product of a prime and a powerful number not divisible by that prime. - Franklin T. Adams-Watters, Jul 25 2006
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
28 has the prime factorization of 2^2 * 7^1. 28 is therefore included in this sequence because there is exactly one prime raised to an exponent of 1 in 28's prime factorization.
MATHEMATICA
Select[Range@147, Count[FactorInteger@#, 1, 2] == 1 &] (* Robert G. Wilson v, Jul 25 2006 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, Jul 23 2006
EXTENSIONS
More terms from Robert G. Wilson v and Franklin T. Adams-Watters, Jul 25 2006
STATUS
approved