A004626 Divisible only by primes congruent to 3 mod 8.

1, 3, 9, 11, 19, 27, 33, 43, 57, 59, 67, 81, 83, 99, 107, 121, 129, 131, 139, 163, 171, 177, 179, 201, 209, 211, 227, 243, 249, 251, 283, 297, 307, 321, 331, 347, 361, 363, 379, 387, 393, 417, 419, 443, 467, 473

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Programs

Magma

[n: n in [1..1000] | forall{d: d in PrimeDivisors(n) | d mod 8 eq 3}]; // Vincenzo Librandi, Aug 20 2012

Mathematica

 ok[1]=True;ok[n_]:=And@@(Mod[#,8]==3&)/@FactorInteger[n][[All,1]];Select[Range[3000],ok] (* Vincenzo Librandi, Aug 20 2012 *)

Extensions

Offset changed from 0 to 1 by Vincenzo Librandi, Aug 20 2012