MANY HARD EXAMPLES FOR RESOLUTION

被引:240
作者
CHVATAL, V [1 ]
SZEMEREDI, E [1 ]
机构
[1] HUNGARIAN ACAD SCI,INST MATH,H-1361 BUDAPEST 5,HUNGARY
关键词
Mathematical Techniques - Graph Theory - Probability - Random Processes;
D O I
10.1145/48014.48016
中图分类号
TP3 [计算技术、计算机技术];
学科分类号
0812 ;
摘要
It is proved that for every choice of positive integers c and k such that k ≥ 3 and c2-k ≥ 0.7, there is a positive number Ε such that, with probability tending to 1 as n tends to ∞, a randomly chosen family of cn clauses of size k over n variables is unsatisfiable, but every resolution proof of its unsatisfiability must generate at least (1 + Ε)n clauses. The proof makes use of random hypergraphs.
引用
收藏
页码:759 / 768
页数:10
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