A New Upper Bound for 1324-Avoiding Permutations

نویسنده

Miklós Bóna

چکیده

We prove that the number of 1324-avoiding permutations of length n is less than (7 + 4 √ 3). The novelty of our method is that we injectively encode such permutations by a pair of words of length n over a finite alphabet that avoid a given factor.

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