mini-gmp: mpz_congruent_p and mpz_probab_prime_p

Niels Möller nisse at
Wed Mar 12 13:24:29 UTC 2014

Torbjorn Granlund <tg at> writes:

> I didn't follow this thread too closely, but that code seems to suggest
> that an argument of 5000 makes sense.

I don't think it makes much sense. But I'd like to make sure that
mpz_probab_prime_p returns 1 also in the case case a user passes a prime
of the form k^2 + k + 41 and a ridiculously large reps as input.

> Even the most paranoic of us needn't reps args of more than 50, given
> that the worst pseudoprimes are caught with the probability 3/4 for each
> rep.

In interesting exercise would be to search for composites that are
pseudoprimes to as many as possible of the bases in the sequence k^2 + k
+ 41.


Niels Möller. PGP-encrypted email is preferred. Keyid C0B98E26.
Internet email is subject to wholesale government surveillance.

More information about the gmp-devel mailing list