Note, in my last post, I did not check to see if -56 is really a root.
In trying to check it, one gets real nonsense.
(%i6) subst(x=-56, x^51+x^22+1);
(%o6) -
1437438846217273045233591279433697587696887228686919480393652546754508\
87538187253915320319
(%i7) flt(%);
(%o7) - 1.4374388462172729E+89
On the other hand,
(%i17) modulus: 127;
(%o17) 127
(%i18) polymod(x^51+x^22+1);
51 22
(%o18) x + x + 1
(%i19) factor(%)$
(%i20) p(u):= subst(x=u,factor(%o18));
(%o20) p(u) := subst(x = u, factor(%o18))
(%i21) p(-56);
(%o21) 0
(%i22)
So, it seemed to find the root symbolically.
For what it's worth.
-sen
---------------------------------------------------------------------------
| Sheldon E. Newhouse | e-mail: sen1 at math.msu.edu |
| Mathematics Department | |
| Michigan State University | telephone: 517-355-9684 |
| E. Lansing, MI 48824-1027 USA | FAX: 517-432-1562 |
---------------------------------------------------------------------------
On Mon, 12 Feb 2007, sen1 at math.msu.edu wrote:
> Works for me,
>
> It found the factor
> (x + 56). The rest is the associated degree 50 factor. I cut and
> pasted it in but the text got pasted in strangely, so I didn't think it worth
> including in this post.
>
>
> -sen
>
> (%i1) build_info();
>
> Maxima version: 5.11.0
> Maxima build date: 4:28 1/25/2007
> host type: i686-pc-linux-gnu
> lisp-implementation-type: GNU Common Lisp (GCL)
> lisp-implementation-version: GCL 2.6.7
>
> (%o1)
> (%i2) modulus: 127;
> (%o2) 127
> (%i3) factor(x^51+x^22+1);
>
> (%o3) (x + 56) (degree 50 polynomial . . . )
>
>
> ---------------------------------------------------------------------------
> | Sheldon E. Newhouse | e-mail: sen1 at math.msu.edu |
> | Mathematics Department | |
> | Michigan State University | telephone: 517-355-9684 |
> | E. Lansing, MI 48824-1027 USA | FAX: 517-432-1562 |
> ---------------------------------------------------------------------------
>
> On Mon, 12 Feb 2007, Fabrizio Caruso wrote:
>
>> Hi
>>
>> I found this problem with factor:
>>
>> modulus:197;
>> factor(x^51+x^22+1);
>> "
>> Maxima encountered a Lisp error:
>>
>> Error during processing of --eval option "(cl-user::run)":
>>
>> Argument X is not a NUMBER: NIL
>>
>> Automatically continuing.
>> To reenable the Lisp debugger set *debugger-hook* to nil.
>> "
>>
>>
>> Remark: I am using 5.10.99rc2 with sbcl.
>> compiled for Ubuntu.
>>
>> Fabrizio
>> _______________________________________________
>> Maxima mailing list
>> Maxima at math.utexas.edu
>> http://www.math.utexas.edu/mailman/listinfo/maxima
>>
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