John Cremona (Maths) on Thu, 10 Sep 1998 09:11:24 +0100

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Re: Another bug?

Gerhard's explanantion does not quite solve Igor's problem, since the
content and leading coefficients of the factors (in Z[X]) are both
normalized to be positive, so that factorback() gives a primitive poly
with positive leading coefficient, and the identity

	   f == content(f)*factorback(factor(f))

only holds when f has positive leading coefficient, otherwise the
right hand side gives -f.  Beware!


John Cremona
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