Karim Belabas on Mon, 12 Sep 2005 19:52:46 +0200


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Re: better isprime cross-over test 

* Bill Allombert [2005-09-02 12:26]:
> Hello PARI-dev,
> 
> isprime include a mechanism to choose between the p-1 test and APRCL
> test. However it does not take into account the fact that the p-1 test 
> only need p-1 to be factored up to sqrt(p-1).
> 
> This patch changes this, which should make the p-1 test used far more
> often.
> 
> One example where it make a difference: isprime(2^127-1) 

Applied to CVS

Thanks!

    Karim.
-- 
Karim Belabas                  Tel: (+33) (0)1 69 15 57 48
Universite Bordeaux 1          Fax: (+33) (0)1 69 15 60 19
351, cours de la Liberation    http://www.math.u-bordeaux.fr/~belabas/
F-33405 Talence (France)       http://pari.math.u-bordeaux.fr/  [PARI/GP]