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A141231 Positive integers whose prime factorizations contain only primes from A001122. 0
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 (list; graph; refs; listen; history; text; internal format)
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: A285141 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

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Last modified October 16 03:37 EDT 2019. Contains 328040 sequences. (Running on oeis4.)