Optimal strong Mal’cev conditions for omitting type 1 in locally finite varieties

نویسندگان

  • Keith Kearnes
  • Petar Marković
  • Ralph McKenzie
چکیده

We show that the class of locally finite varieties omitting type 1 has the following properties. This class (1) is definable by an idempotent, linear, strong Mal’cev condition in a language with one 4-ary function symbol. (2) is not definable by an idempotent, linear, strong Mal’cev condition in a language with only one function symbol of arity strictly less than 4. (3) is definable by an idempotent, linear, strong Mal’cev condition in a language with two 3-ary function symbols. (4) is not definable by an idempotent, linear, strong Mal’cev condition in a language with function symbols of arity less than 4 unless at least two of the symbols have arity 3.

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تاریخ انتشار 2012