Pattern-avoiding involutions: exact and asymptotic enumeration
نویسندگان
چکیده
We consider the enumeration of pattern-avoiding involutions, focusing in particular on sets defined by avoiding a single pattern of length 4. We directly enumerate the involutions avoiding 1342 and the involutions avoiding 2341. As we demonstrate, the numerical data for these problems exhibits some surprising behavior. This strange behavior even provides some very unexpected data related to the number of 1324-avoiding permutations.
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 64 شماره
صفحات -
تاریخ انتشار 2016