A141231 Positive integers whose prime factorizations contain only primes from A001122.

3, 5, 9, 11, 13, 15, 19, 25, 27, 29, 33, 37, 39, 45, 53, 55, 57, 59, 61, 65, 67, 75, 81, 83, 87, 95, 99, 101, 107, 111, 117, 121, 125, 131, 135, 139, 143, 145, 149, 159, 163, 165, 169, 171, 173, 177, 179, 181, 183, 185, 195, 197, 201, 209, 211, 225, 227, 243, 247, 249

Offset

1,1

Links

Table of n, a(n) for n=1..60.

Mathematica

aQ[n_] := Length[Select[FactorInteger[n][[;; , 1]], # > 1 && PrimitiveRoot@# != 2 &]] == 0; Select[Range[2, 250], aQ] (* Amiram Eldar, Dec 09 2018 *)

Prog

(PARI) isokp(p) = znorder(Mod(2, p))==(p-1);
isok(n) = {if ((n>1) && (n % 2), my(f=factor(n)); #select(x->isokp(x), f[, 1]) == #f~; , 0); } \\ Michel Marcus, Dec 09 2018

Crossrefs

Cf. A001122, A000040.

Sequence in context: A329095 A319009 A294427 * A287344 A047623 A190523

Adjacent sequences: A141228 A141229 A141230 * A141232 A141233 A141234

Keyword

nonn

Author

Vladimir Shevelev, Jun 16 2008

Extensions

More terms from Michel Marcus, Dec 09 2018

Status

approved