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1. • CommentRowNumber1.
   • CommentAuthorGuest
   • CommentTime7 days ago
   • PermaLink
   Author: Guest
   Format: MarkdownItexstarted [[pointed commutative invertible semigroups]] <a href="https://ncatlab.org/nlab/revision/pointed+commutative+invertible+semigroup/1">v1</a>, <a href="https://ncatlab.org/nlab/show/pointed+commutative+invertible+semigroup">current</a>

   started pointed commutative invertible semigroups

   v1, current

2. • CommentRowNumber2.
   • CommentAuthorTodd_Trimble
   • CommentTime7 days ago
   • PermaLink
   Author: Todd_Trimble
   Format: MarkdownItexYou say the category is not the same as the category of abelian groups, which is true enough, but isn't it equivalent to the category of pointed abelian groups, equivalently the undercategory or co-slice $\mathbb{Z} \downarrow Ab$? "Pointed commutative invertible semigroup" just sounds so long-winded, if "pointed abelian group" would do. Do other people use this phrase?

   You say the category is not the same as the category of abelian groups, which is true enough, but isn’t it equivalent to the category of pointed abelian groups, equivalently the undercategory or co-slice $\mathbb{Z} \downarrow Ab$? “Pointed commutative invertible semigroup” just sounds so long-winded, if “pointed abelian group” would do. Do other people use this phrase?