Undecidability of the Horn Clause Finite Implication Problem ?
نویسنده
چکیده
We prove that the set IMPL of such pairs < H; G > of Horn clauses, that H nitely implies G (i.e. G is true in all the nite structures in which H is true), is not recursive. Moreover, we prove that sets co-IMP L and RES=f< H; G > G can be derived from H by resolution g are recursively inseparable.
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تاریخ انتشار 1995