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A219030 Powers of odd primes (exponent > 1) for which 2 is not a primitive root. 1
49, 289, 343, 529, 961, 1681, 1849, 2209, 2401, 4913, 5041, 5329, 6241, 7921, 9409, 10609, 11881, 12167, 12769, 16129, 16807, 18769, 22801, 24649, 27889, 29791, 36481, 37249, 39601, 49729, 52441, 54289, 57121, 58081, 63001, 66049, 68921, 69169, 73441 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..39.

PROG

(PARI) for(n=3, 100000, if(n%2==1&&isprime(n)==0&&znorder(Mod(2, n))!=eulerphi(n)&&matsize(factor(n))[1]==1, print1(n", ")))

(PARI) list(lim)=my(v=List(), L=log(lim+.5)); forprime(p=3, sqrtint(lim\1), for(e=2, L\log(p), if(znorder(Mod(2, p^e))<p^(e-1)*(p-1), listput(v, p^e)))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Nov 12 2012

CROSSREFS

Cf. A167791, A216848, A108989.

Sequence in context: A017246 A020274 A158248 * A167719 A239211 A198437

Adjacent sequences:  A219027 A219028 A219029 * A219031 A219032 A219033

KEYWORD

nonn

AUTHOR

V. Raman, Nov 10 2012

STATUS

approved

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Last modified August 11 03:22 EDT 2020. Contains 336421 sequences. (Running on oeis4.)