A071822 Numbers whose largest prime factor is of the form 4k+3.

3, 6, 7, 9, 11, 12, 14, 18, 19, 21, 22, 23, 24, 27, 28, 31, 33, 35, 36, 38, 42, 43, 44, 46, 47, 48, 49, 54, 55, 56, 57, 59, 62, 63, 66, 67, 69, 70, 71, 72, 76, 77, 79, 81, 83, 84, 86, 88, 92, 93, 94, 95, 96, 98, 99, 103, 105, 107, 108, 110, 112, 114, 115, 118, 121, 124

Offset: 1

Author

Benoit Cloitre, Jun 07 2002

Keywords

• easy
• nonn

Links

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

Crossrefs

Cf. A004767, A006530, A071821.

Programs

Mathematica

Select[Range[125], Mod[FactorInteger[#][[-1,1]], 4] == 3 &] (* Amiram Eldar, May 04 2022 *)

PARI

for(n=2,200,if((component(component(factor(n),1),omega(n))-3)%4==0,print1(n,",")))

Formula

Numbers k such that A006530(k) == 3 (mod 4).