A065201 Numbers having a non-maximal prime-factor with exponent greater than 1.

12, 20, 24, 28, 36, 40, 44, 45, 48, 52, 56, 60, 63, 68, 72, 76, 80, 84, 88, 90, 92, 96, 99, 100, 104, 108, 112, 116, 117, 120, 124, 126, 132, 135, 136, 140, 144, 148, 152, 153, 156, 160, 164, 168, 171, 172, 175, 176, 180, 184, 188, 189, 192, 196, 198, 200

Offset: 1

Author

Reinhard Zumkeller, Oct 21 2001

Keywords

• nonn

Comments

If k is a term so is every positive multiple of k. The primitive elements are A096156.

Examples

			a(4) = 28 = 2^2 * 7 as 2 < 7.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Complement of A065200. Cf. A065202, A096156.

Programs

Mathematica

q[k_] := Max[Most[FactorInteger[k][[;;, 2]]]] > 1; Select[Range[200], q] (* Amiram Eldar, Mar 19 2025 *)

PARI

isok(k) = {my(e = factor(k)[,2]); #e > 1 && vecmax(e[1..#e-1]) > 1;} \\ Amiram Eldar, Mar 19 2025

Extensions

Edited by Franklin T. Adams-Watters, Oct 27 2006