Some Remarks on Semigroup Presentations
B. Neumann · Canadian Journal of Mathematics · 1967
Let a semigroupAbe given by generators a1, a2, … , adand defining relationsu1= v1, u2= v2, … ,ue=vebetween these generators, theui,vibeing words in the generators. We then have apresentationofA, and write The same generators with the same relations can also be interpreted as the presentation of a group, for which we write