A PROOF OF OKNINSKI AND PUTCHA'S THEOREM

摘要

Okninski and Putcha proved that any finite semigroup S is an amalgamation base for all finite semigroups if the J-classes of S are linearly ordered and the semigroup algebra R [S] over C has a zero Jacobson radical. As its consequence they proved that every finite inverse semigroup U whose all of the J-classes form a chain is an amalgamation base for finite semigroups. In this paper we give another proof of the result for finite inverse semigroups by making use of semigroup representations only.