Undecidable Relativizations of Algebras of Relations
نویسندگان
چکیده
In this paper we show that relativized versions of relation set algebras and cylindric set algebras have undecidable equational theories if we include coordinatewise versions of the counting operations into the similarity type. We apply these results to the guarded fragment of first-order logic. ?
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ورودعنوان ژورنال:
- J. Symb. Log.
دوره 64 شماره
صفحات -
تاریخ انتشار 1999