[Axiom-developer] [#191 exquo and therefore gcd cannot handle UP(x, EXPR INT)] $2^{a2}$ vs $4^a$

[billpage]

Changes 
http://page.axiom-developer.org/zope/mathaction/191ExquoAndThereforeGcdCannotHandleUPXEXPRINT/diff
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Notice the result of the simplification:
\begin{axiom}
p:=(x-2^a)::UP(x, EXPR INT)
q:=simplify((x-2^a)*(x+2^a))::UP(x, EXPR INT)
gcd(p, q)
\end{axiom}
Without the simplification:
\begin{axiom}
r:=((x-2^a)*(x+2^a))::UP(x, EXPR INT)
gcd(p, r)
\end{axiom}
The problem seems to be that Axiom does not always treat $2^{a2}$
the same as $4^a$.
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forwarded from http://page.axiom-developer.org/zope/mathaction/address@hidden