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From: Makoto Hamana <hamana@cs.gunma-u.ac.jp>
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Subject: Re: [categories] initial algebra question
Date: Thu, 29 Jan 2009 17:27:27 +0900
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> Date: Wed, 28 Jan 2009 19:31:35 +0000
> From: Paul Levy <P.B.Levy@cs.bham.ac.uk>

> Does anybody know a reference for the following (very easy) result?
> Let C and D be categories, and let F:C-->D and G:D-->C be functors.
> If (c,theta) is an initial algebra for GF, then (Fc, F theta) is an initial algebra for FG.

It is mentioned as Proposition 5.3 of

Alex Simpson and Gordon Plotkin,
Complete Axioms for Categorical Fixed-point Operators, LICS 2000.

Best Regards,
Makoto Hamana