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A070270 Primes for which the smallest positive primitive root is even and nonprime. 1
41, 109, 151, 229, 251, 271, 313, 337, 367, 733, 761, 971, 991, 1021, 1031, 1069, 1289, 1297, 1303, 1429, 1471, 1489, 1759, 1783, 1789, 1811, 1871, 1873, 1879, 2137, 2411, 2441, 2551, 2749, 2791, 2971, 3001, 3061, 3079, 3109, 3221, 3229, 3251, 3301 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

MATHEMATICA

Select[Prime[Range[500]], EvenQ[PrimitiveRoot[#]]&&PrimitiveRoot[#]!=2&] (* Harvey P. Dale, Jul 31 2015 *)

PROG

(PARI) forprime(n=1, 5000, if((-1)^(lift(znprimroot(n))*(1-isprime(lift(znprimroot(n)))))==1+isprime(lift(znprimroot(n))), print1(n, ", ")))

CROSSREFS

Cf. A047936, A001918.

Sequence in context: A211494 A142054 A279213 * A001125 A116509 A105389

Adjacent sequences:  A070267 A070268 A070269 * A070271 A070272 A070273

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre, May 09 2002

STATUS

approved

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Last modified May 26 04:43 EDT 2022. Contains 354074 sequences. (Running on oeis4.)