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A216848 Odd numbers for which 2 is not a primitive root. 2
7, 15, 17, 21, 23, 31, 33, 35, 39, 41, 43, 45, 47, 49, 51, 55, 57, 63, 65, 69, 71, 73, 75, 77, 79, 85, 87, 89, 91, 93, 95, 97, 99, 103, 105, 109, 111, 113, 115, 117, 119, 123, 127, 129, 133, 135, 137, 141, 143, 145, 147, 151, 153, 155, 157, 159, 161, 165, 167 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..59.

MATHEMATICA

nn = 200; Select[Range[3, nn, 2], PrimitiveRoot[#] =!= 2 &] (* T. D. Noe, Sep 19 2012 *)

PROG

(PARI) forstep(p=3, 200, 2, if(znorder(Mod(2, p))!=eulerphi(p), print(p)))

CROSSREFS

Cf. A002326, A001122, A216838.

Sequence in context: A204740 A244536 A237054 * A065566 A329485 A154618

Adjacent sequences:  A216845 A216846 A216847 * A216849 A216850 A216851

KEYWORD

nonn

AUTHOR

V. Raman, Sep 17 2012

STATUS

approved

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Last modified January 28 06:29 EST 2020. Contains 331317 sequences. (Running on oeis4.)