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A239901
Primes p such that ((p-1)/4)! is a primitive root mod p.
1
13, 17, 41, 53, 101, 137, 149, 277, 313, 317, 389, 401, 433, 449, 521, 557, 569, 673, 677, 701, 761, 769, 809, 857, 877, 953, 977, 1009, 1129, 1213, 1277, 1297, 1361, 1373, 1409, 1489, 1493, 1549, 1613, 1637, 1657, 1697, 1709, 1741, 1789, 1861, 1873, 1901
OFFSET
1,1
REFERENCES
John B. Cosgrave and Karl Dilcher, The multiplicative orders of certain Gauss factorials, II, Preprint, 2014.
LINKS
PROG
(PARI)
isok(n) = {
ret = 1;
if(n % 4 == 1 && isprime(n),
m = (n - 1) / 4;
r = m! % n;
f = factor(n - 1);
l = length(f~);
for(i=1, l,
if(Mod(r^((n-1)/f[i, 1]), n) == 1,
ret = 0;
);
);
,
ret = 0;
);
ret;
} \\ Hiroaki Yamanouchi, Sep 30 2014
CROSSREFS
Sequence in context: A043113 A043893 A279392 * A068497 A125524 A156553
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Apr 06 2014
EXTENSIONS
a(11)-a(48) from Hiroaki Yamanouchi, Sep 30 2014
STATUS
approved