Improved inclusion-exclusion identities via closure operators

نویسنده

  • Klaus Dohmen
چکیده

Improved inclusion-exclusion identities via closure operators Klaus Dohmen Department of Computer Science, Humboldt-University Berlin, Unter den Linden 6, D-10099 Berlin, Germany E-mail: [email protected] received March 24, 1999, revised September 6, 1999, accepted April 15, 2000. Let be a finite family of sets. We establish an improved inclusion-exclusion identity for each closure operator on the power set of having the unique base property. The result generalizes three improvements of the inclusion-exclusion principle as well as Whitney’s broken circuit theorem on the chromatic polynomial of a graph.

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عنوان ژورنال:
  • Discrete Mathematics & Theoretical Computer Science

دوره 4  شماره 

صفحات  -

تاریخ انتشار 2000