Linear Extensions of N-free Orders
نویسندگان
چکیده
We consider the number of linear extensions of an N-free order P . We give upper and lower bounds on this number in terms of parameters of the corresponding arc diagram. We propose a dynamic programming algorithm to calculate the number. The algorithm is polynomial if a new parameter called activity is bounded by a constant. The activity can be bounded in terms of parameters of the arc diagram. Mathematics Subject Classifications (2000) 06A05, 06A07, 68R99.
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ورودعنوان ژورنال:
- Order
دوره 32 شماره
صفحات -
تاریخ انتشار 2015