Karim Belabas on Wed, 18 Jul 2012 01:46:47 +0200


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Re: 2.5.1, 2.4.3 are missing solutions in conditional thue


* Georgi Guninski [2012-07-07 15:45]:
> Some more testcases for 2.5.1/2.4.3:
> 
> pp=x^3 - 20*x^2 + 100*x + 1;a=3^3
> pp=x^3 - 20*x^2 + 100*x + 1;a=2^3
> pp=x^3 - 18*x^2 + 81*x + 1;a=2^3
> pp=x^3 - 6*x^2 + 9*x + 1;a=1
> pp=x^3 - 20*x^2 + 100*x + 1;a=1
> 
> (For $a=1$ 2.4.3 doesn't give any warning).
> 
> On Sat, Jul 07, 2012 at 03:34:50PM +0300, Georgi Guninski wrote:
> > 2.5.1 and 2.4.3 on ubuntu x86_64.
> > 
> > ? p=x^3 - 18*x^2 + 81*x + 1;a=3^3
> > %1 = 27
> > ? t=thue(thueinit(p,0),a);[#t,t]
> > %2 = [3, [[0, 3], [3, 0], [19, 2]]]
> > ? t=thue(thueinit(p,1),a);[#t,t]
> > %3 = [4, [[0, 3], [3, 0], [27, 3], [19, 2]]]
> > 
> > 2.5.1 doesn't give warning, 2.4.3 mentions GRH (surely incorrect).

Guillaume Hanrot just sent a patch: all these problems are now fixed in
master (2.6.*), as well as the long-standing bug #951:

  http://pari.math.u-bordeaux1.fr/cgi-bin/bugreport.cgi?bug=951

Thanks for your report, and many thanks to Guillaume for the quick patch!

    K.B.

commit 672670b66eb3718711cd0e9c81cc01ca4417cefa
Author: Karim Belabas <Karim.Belabas@math.u-bordeaux1.fr>
Date:   Wed Jul 18 01:40:53 2012 +0200

    GH 86- missing solutions in thue(), e.g. thue(thueinit(x^3+92*x+1),3^3)
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