A334146 Numbers with at least two prime factors greater than 3 counted with multiplicity.

25, 35, 49, 50, 55, 65, 70, 75, 77, 85, 91, 95, 98, 100, 105, 110, 115, 119, 121, 125, 130, 133, 140, 143, 145, 147, 150, 154, 155, 161, 165, 169, 170, 175, 182, 185, 187, 190, 195, 196, 200, 203, 205, 209, 210, 215, 217, 220, 221, 225, 230, 231, 235, 238, 242

Offset: 1

Author

Aidan Clarke, Apr 16 2020

Keywords

• nonn
• easy

Examples

			25 = 5*5
35 = 5*7
49 = 7*7
50 = (2)*5*5
55 = 5*11
65 = 5*13
70 = (2)*5*7
75 = (3)*5*5
		

Crossrefs

Cf. A093641.

Programs

Mathematica

Select[Range[250], CompositeQ[# / 2^IntegerExponent[#, 2] / 3^IntegerExponent[#, 3]] &] (* Amiram Eldar, May 01 2020 *)

PARI

is(n)=n>>=valuation(n,2);n/=3^valuation(n,3);n>1 && !isprime(n) \\ Charles R Greathouse IV, Apr 16 2020

Formula

a(n) ~ n. - Charles R Greathouse IV, Apr 16 2020