Resolution Proofs of Generalized Pigeonhole Principles
نویسندگان
چکیده
We extend results of A. Haken to give an exponential lower bound on the size of resolution proofs for propositional formulas encoding a generalized pigeonhole principle. These propositional formulas express the fact that there is no one-one mapping from c ·n objects to n objects when c > 1. As a corollary, resolution proof systems do not p -simulate constant formula depth Frege proof systems.
منابع مشابه
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 62 شماره
صفحات -
تاریخ انتشار 1988