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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeJun 26th 2011
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   Author: Urs
   Format: MarkdownItexhave split off the definition of [[umbrella category]] from [[subterminal object]]

   have split off the definition of umbrella category from subterminal object

2. • CommentRowNumber2.
   • CommentAuthorMike Shulman
   • CommentTimeJun 26th 2011
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   Author: Mike Shulman
   Format: MarkdownItexWhat are those for?

   What are those for?

3. • CommentRowNumber3.
   • CommentAuthorUrs
   • CommentTimeJun 26th 2011
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   Author: Urs
   Format: MarkdownItexI don't know. Zoran did introduce this in [Rev #5](http://ncatlab.org/nlab/revision/diff/subterminal+object/5).

   I don’t know. Zoran did introduce this in Rev #5.

4. • CommentRowNumber4.
   • CommentAuthorzskoda
   • CommentTimeJun 27th 2011
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   Author: zskoda
   Format: MarkdownItexHierarchy of some algebraic structures is described by such categories, kind of free object at the top and the bottom ones are subterminal -- every object is kind of in between, on at least one "strand". For example, what I call generalized smash products of a Hopf algebra and an algebra form such a category.

   Hierarchy of some algebraic structures is described by such categories, kind of free object at the top and the bottom ones are subterminal – every object is kind of in between, on at least one “strand”. For example, what I call generalized smash products of a Hopf algebra and an algebra form such a category.