Sharper estimates for the number of permutations avoiding a layered or decomposable pattern
نویسنده
چکیده
We present two methods that for infinitely many patterns q provide better upper bounds for the number Sn(q) of permutations of length n avoiding the pattern q than the recent general result of Marcus and Tardos. While achieving that, we define an apparently new decomposition of permutations .
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تاریخ انتشار 2004