On the complexity of enumerating pseudo-intents
نویسندگان
چکیده
We investigate whether the pseudo-intents of a given formal context can efficiently be enumerated. We show that they cannot be enumerated in a specified lexicographic order with polynomial delay unless p = np. Furthermore we show that if the restriction on the order of enumeration is removed, then the problem becomes at least as hard as enumerating minimal transversals of a given hypergraph. We introduce the notion of minimal pseudo-intents and show that recognizing minimal pseudo-intents is polynomial. Despite their less complicated nature, surprisingly it turns out that minimal pseudo-intents cannot be enumerated in output-polynomial time unless p = np.
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ورودعنوان ژورنال:
- Discrete Applied Mathematics
دوره 159 شماره
صفحات -
تاریخ انتشار 2011