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A100142
Numbers of prime primitive roots associated with A100141(n).
2
2, 2, 2, 3, 5, 7, 5, 3, 7, 7, 11, 13, 23, 19, 17, 29, 31, 23, 41, 29, 31, 41, 29, 47, 37, 43, 41, 71, 47, 79, 83, 89, 43, 83, 59, 73, 127, 83, 109, 67, 89, 101, 89, 89, 97, 107, 113, 151, 79, 79, 107, 113, 149, 157, 191, 193, 199, 113, 197, 191, 211, 113, 227, 131, 193, 241
OFFSET
1,1
LINKS
MATHEMATICA
f[n_] := Module[{p = Select[PrimitiveRootList[n], PrimeQ], m}, m = Length[p]; If[MemberQ[p, m] && PrimeQ[m], m, 0]]; Select[f /@ Range[3000], # > 0 &] (* Amiram Eldar, Sep 25 2021 *)
CROSSREFS
Cf. A100141.
Sequence in context: A239470 A320786 A126111 * A296103 A247907 A122789
KEYWORD
easy,nonn
AUTHOR
Sven Simon, Nov 07 2004
EXTENSIONS
Offset corrected and a(2) inserted by Amiram Eldar, Sep 25 2021
STATUS
approved