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A167806
Numbers with primitive root -10.
20
3, 17, 29, 31, 43, 61, 67, 71, 83, 97, 107, 109, 113, 149, 151, 163, 181, 191, 193, 199, 227, 229, 233, 257, 269, 283, 289, 307, 311, 313, 337, 347, 359, 389, 431, 433, 439, 443, 461, 467, 479, 509, 523, 541, 563, 577, 587, 593, 599, 631, 683, 701, 709, 719
OFFSET
1,1
COMMENTS
Note that the term 289 is not a prime and therefore does not appear in A007348. - Robert G. Wilson v, Aug 18 2014
LINKS
MATHEMATICA
pr=-10; Select[Range[2, 2000], MultiplicativeOrder[pr, # ] == EulerPhi[ # ] &]
PROG
(PARI) is(n)=if(gcd(n, 10)>1, return(0)); my(p=eulerphi(n)); znorder(Mod(-10, n), p)==p \\ Charles R Greathouse IV, Nov 25 2014
CROSSREFS
Cf. A007348 (primes with primitive root -10).
Sequence in context: A192538 A045436 A296925 * A007348 A105912 A249374
KEYWORD
nonn
AUTHOR
T. D. Noe, Nov 12 2009
STATUS
approved