It gets worse:  (with GP/PARI 2.4.2):

? default(debug,2)
%5 = 2
? p=nextprime(10^20)
%6 = 100000000000000000039
? isprime(p)
  *** isprime: Warning: IFAC: untested integer declared prime.
        507526619771207
%7 = 1

-- so one call to isprime(), which supposedly proves a proof, involves
further calls (presumably) to fact() whose reults are not proved.

Another email to pari-dev is in order...

John

On 9/7/07, Bill Hart <[EMAIL PROTECTED]> wrote:
>
> The number field code in Pari relies on factoring the discriminant
> often using MPQS. In particular if you turn debugging mode on, you get
> warnings like this:
>
>   *** bnfclassunit: Warning: IFAC: untested integer declared prime.
>         10762727634633706239259776012492757340083
>
> So basically the number field code is no more reliable than a probable
> prime test.
>
> This is bad news if you only want unconditional results from Pari. It
> may not be trivial to get unconditional results from all Pari
> functions.
>
> Bill.
>
>
>
> >
>


-- 
John Cremona

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