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categories: Re: lluf
The term commonly used for the corresponding concept to lluf for groupoids
is `wide'. I won't give a preference!
`Representative subgroupoid' is used as for categories. Both occur in my
1968 book on topology, and I seem to remember the term wide was new.
Ronnie Brown
Charles Wells wrote:
>
> "Lluf" is "full" written backward. Full means if the subcategory has two
> objects it has all the arrows between them. Lluf means the subcategory has
> all the objects of the containing category but not necessary all the
> arrows. Lluf is not a categorical notion. The more useful notion is
> REPRESENTATIVE subcategory. D is a representative subcategory of C if
> every object of C is isomorphic to an object of D. I think some writers
> have used "extensive" for "representative" but I don't have a reference. I
> don't know the history of those words.
>
> Charles Wells,
> Emeritus Professor of Mathematics, Case Western Reserve University
> Affiliate Scholar, Oberlin College
> Send all mail to:
> 105 South Cedar St., Oberlin, Ohio 44074, USA.
> email: charles@freude.com.
> home phone: 440 774 1926.
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> personal website: http://www.oberlin.net/~cwells/index.html
> genealogical website:
> http://familytreemaker.genealogy.com/users/w/e/l/Charles-Wells/
> NE Ohio Sacred Harp website: http://www.oberlin.net/~cwells/sh.htm
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