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/*
Copyright (C) 2016 Pascal Molin
This file is part of FLINT.
FLINT is free software: you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License (LGPL) as published
by the Free Software Foundation; either version 3 of the License, or
(at your option) any later version. See <https://www.gnu.org/licenses/>.
*/
#include "dirichlet.h"
ulong
dirichlet_group_num_primitive(const dirichlet_group_t G)
{
if (G->q % 4 == 2)
return 0;
else
{
slong k;
ulong n = 1;
/* no overflow since result < G->q */
for (k = (G->neven == 2); k < G->num; k++)
{
ulong p = G->P[k].p, e = G->P[k].e;
if (e == 1)
n *= p - 2;
else
n *= (p * (p - 2) + 1) * n_pow(p, e - 2);
}
return n;
}
}