On the complexity of enumerating pseudo-intents

نویسندگان

  • Felix Distel
  • Baris Sertkaya
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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عنوان ژورنال:
  • Discrete Applied Mathematics

دوره 159  شماره 

صفحات  -

تاریخ انتشار 2011