Igor Schein on Thu, 28 Jan 1999 14:22:39 -0500

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Re: polgalois()

On Tue, Jan 26, 1999 at 11:55:39AM -0500, Igor Schein wrote:
> Hi,
> polgalois(x^11+2) runs forever.  I haven't had patience to see if it'd
> ever finish.  Is it expectable?
> Thanks
> Igor

Looks like it might finish after a very long time ( at least 2
Ultra-60 CPU days, according to a very rough estimate ). 

Indeed, here's the loop:

galois.c:862:          for (nocos=1; nocos<=nbcos; nocos++)

For 11-degree polynomial nbcos is 11!, which is ~400M.

So it's one loooong loop.

polgalois() never gets inside this loop of all other polynomials I
tried, including degree-8,9,10 and degree-11 polynomials.  So it's
either a bug or bad coding.  For comparison, I tried an equivalent
of polgalois() in GAP software, and it came back with an answer in a
short time.