Talk:Variety (universal algebra)

From Wikipedia, the free encyclopedia

[edit] Someone please define subvariety

In this entry, the word "subvariety" appears without explanation. Would someone please define it? Better yet, would someone create a brief entry for the term, and blue link it to this entry? It is fascinating to read that groups are not necessarily subvarieties of semigroups, but that abelian groups are all subvarieties of groups. Are Boolean algebras subvarieties of lattices? Of commutative monoids?202.36.179.65 09:20, 25 September 2007 (UTC)

[edit] arity?

What is arity? LilHelpa (talk) 19:44, 3 March 2009 (UTC)

Arity is the number of arguments an operation takes. Constants are 0-ary, negation and inversion are 1-ary (unary), addition, subtraction, multiplication, and division are 2-ary (binary), and the triple product is 3-ary. JackSchmidt (talk) 20:12, 3 March 2009 (UTC)