A Pumping Lemma for Pushdown Graphs of Any Level
نویسنده
چکیده
We present a pumping lemma for the class of ε-contractions of pushdown graphs of level n, for each n. A pumping lemma was proposed by Blumensath, but there is an irrecoverable error in his proof; we present a new proof. Our pumping lemma also improves the bounds given in the invalid paper of Blumensath. 1998 ACM Subject Classification F.1.1 Models of Computation
منابع مشابه
A Pumping Lemma for Collapsible Pushdown Graphs of Level 2
We present a pumping lemma for the class of collapsible pushdown graphs of level 2. This pumping lemma even applies to the ε-contractions of level 2 collapsible pushdown graphs. Our pumping lemma also improves the bounds of Hayashi’s pumping lemma for indexed languages. 1998 ACM Subject Classification F.1.1 Models of Computation
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تاریخ انتشار 2012