A074595 Number of prime factors of numbers that are not prime powers (with multiplicity).

2, 2, 3, 2, 2, 3, 3, 2, 2, 4, 2, 3, 3, 2, 2, 2, 4, 2, 2, 4, 3, 3, 3, 2, 5, 3, 2, 3, 4, 2, 4, 2, 2, 4, 2, 3, 2, 3, 3, 2, 3, 5, 2, 3, 3, 2, 3, 5, 2, 4, 2, 2, 2, 4, 4, 2, 3, 2, 2, 2, 6, 3, 3, 4, 3, 4, 3, 2, 5, 3, 2, 5, 3, 2, 3, 3, 2, 2, 5, 2, 2, 3, 4, 2, 3, 4, 2, 2, 4, 4, 3, 4, 2, 2, 2, 6, 2, 2, 3, 3, 4, 4, 3, 3, 2

Offset: 1

Author

Reinhard Zumkeller, Aug 25 2002

Keywords

• nonn

Links

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

Crossrefs

Cf. A001222, A024619, A074594, A074592, A074593.

Programs

Mathematica

s[n_] := Module[{f = FactorInteger[n]}, If[Length[f] > 1, Total[f[[;; , 2]]], Nothing]]; Array[s, 200] (* Amiram Eldar, Oct 10 2024 *)

Formula

a(n) = A001222(A024619(n)).