OFFSET
1,1
REFERENCES
John B. Cosgrave and Karl Dilcher, The multiplicative orders of certain Gauss factorials, II, Preprint, 2014.
LINKS
Hiroaki Yamanouchi, Table of n, a(n) for n = 1..10000
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
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Apr 06 2014
EXTENSIONS
a(11)-a(48) from Hiroaki Yamanouchi, Sep 30 2014
STATUS
approved