Permutations Containing and Avoiding 123 and 132 Patterns
نویسنده
چکیده
received April 5, 1999, revised May 12, 1999, accepted May 19, 1999. We prove that the number of permutations which avoid 132-patterns and have exactly one 123-pattern, equals (n 2)2n 3 , for n 3. We then give a bijection onto the set of permutations which avoid 123-patterns and have exactly one 132-pattern. Finally, we show that the number of permutations which contain exactly one 123-pattern and exactly one 132-pattern is (n 3)(n 4)2n 5, for n 5.
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عنوان ژورنال:
- Discrete Mathematics & Theoretical Computer Science
دوره 3 شماره
صفحات -
تاریخ انتشار 1999