cado-nfs - Re: [cado-nfs] sqrt error

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Re: [cado-nfs] sqrt error

From: Paul Zimmermann <Paul.Zimmermann@inria.fr>
To: eric.jeancolas@free.fr
Cc: pierrick.gaudry@loria.fr, cado-nfs@inria.fr
Subject: Re: [cado-nfs] sqrt error
Date: Tue, 27 Apr 2021 08:16:51 +0200
Ironport-hdrordr: A9a23:AD5kbKqE5WHEROJcs+9s24saV5rMeYIsi2QD101hICF9WtCEkYSVgP8e1QLohDt5YhEdsPqHP7SNRm6ZyIV85pMfMazncA7tvmapK48K1+rf6hfnHDDz8fMY6Ld4f8FFZuHYIFBmga/BjTWQPM0nxLC8nJyAocf74zNTQRpxa6dmhj0XNi++HldtTAdLQbo1faD32uN9qzCteWsaY62AbxFvY8H4u9bJmJj6CCR2ZSIP1Q/mt0LK1JfKVz2f2A52aUIr/Z4StUzMkwn0/cyYwpWG9iM=

Dear Eric,

> Can you reproduce the problem, or is it related to my installation?

yes I can. It appears it is not so easy to detect a wrong value of N early.
Indeed, in the square root, we divide N by prime factors dividing the leading
coefficient of one of the two polynomials, and we also do trial division up
to 1000000. If we want to detect a wrong value of N early, we would need to
import all that logic in the cado_poly_getm function. I'm not sure we want to
do that.

Best regards,
Paul

[cado-nfs] sqrt error, eric . jeancolas, 04/26/2021
- Re: [cado-nfs] sqrt error, Pierrick Gaudry, 04/26/2021
  - Re: [cado-nfs] sqrt error, eric . jeancolas, 04/26/2021
  - Re: [cado-nfs] sqrt error, eric . jeancolas, 04/26/2021
    - Re: [cado-nfs] sqrt error, Paul Zimmermann, 04/26/2021
      - Re: [cado-nfs] sqrt error, eric . jeancolas, 04/26/2021
        
        Re: [cado-nfs] sqrt error, Paul Zimmermann, 04/26/2021
        
        Re: [cado-nfs] sqrt error, eric . jeancolas, 04/27/2021
        
        Re: [cado-nfs] sqrt error, Paul Zimmermann, 04/27/2021
        
        Re: [cado-nfs] sqrt error, Emmanuel Thomé, 04/27/2021
        Re: [cado-nfs] sqrt error, eric . jeancolas, 04/27/2021

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Re: [cado-nfs] sqrt error