On Centralizers of Monoids

نویسندگان

  • Hajime Machida
  • Ivo G. Rosenberg
  • H. Machida
  • I. G. Rosenberg
چکیده

For a monoid M of k-valued unary operations, the centralizer M∗ is the clone consisting of all k-valued multi-variable operations which commute with every operation in M . First we give a sufficient condition for a monoid M to have the least clone as its centralizer. Then using this condition we determine centralizers of all monoids containing the symmetric group. AMS Mathematics Subject Classification (2000):

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تاریخ انتشار 2005