Derangements on a Ferrers board
نویسندگان
چکیده
We study the derangement number on a Ferrers board B = (n × n) − λ with respect to an initial permutation M , that is, the number of permutations on B that share no common points with M . We prove that the derangement number is independent of M if and only if λ is of rectangular shape. We characterize the initial permutations that give the minimal and maximal derangement numbers for a general Ferrers board, and present enumerative results when λ is a rectangle.
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ورودعنوان ژورنال:
- Discrete Math., Alg. and Appl.
دوره 7 شماره
صفحات -
تاریخ انتشار 2015