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%I #18 Aug 15 2023 17:02:51
%S 2,3,5,7,11,12,13,17,18,19,20,23,24,28,29,31,37,40,41,43,44,45,47,48,
%T 50,52,53,54,56,59,61,63,67,68,71,73,75,76,79,80,83,88,89,92,96,97,98,
%U 99,101,103,104,107,109,112,113,116,117,124,127,131,135,136,137,139,147
%N Positive integers each with exactly 1 unitary prime divisor (i.e., n is included if and only if A056169(n) = 1).
%C 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
%H Amiram Eldar, <a href="/A119251/b119251.txt">Table of n, a(n) for n = 1..10000</a>
%e 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.
%t Select[Range@147, Count[FactorInteger@#, 1, 2] == 1 &] (* _Robert G. Wilson v_, Jul 25 2006 *)
%Y Cf. A001694, A056169.
%K nonn
%O 1,1
%A _Leroy Quet_, Jul 23 2006
%E More terms from _Robert G. Wilson v_ and _Franklin T. Adams-Watters_, Jul 25 2006