A Note on the Proof of Cobham’s Theorem
نویسنده
چکیده
The famous theorem of Cobham says that, for multiplicatively independent integers k and l, any subset of N, which is both kand l-recognizable, is recognizable. Many of its proofs are based on so called Hansel’s lemma stating that such a kand l-recognizable set is syndetic. We consider these proofs and point out that some of them are inadequate.
منابع مشابه
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تاریخ انتشار 2005