, Volume 10, Issue 4, pp 393–396 | Cite as

Solution of an extremal problem for sets using resultants of polynomials

  • A. Blokhuis


A new, short proof is given of the following theorem of Bollobás: LetA1,..., Ah andB1,..., Bh be collections of sets with ∀ i ∶¦Ai¦=r,¦Bi¦=s and ¦Ai∩Bj¦=Ø if and only ifi=j, thenh≤( s r+s ). The proof immediately extends to the generalizations of this theorem obtained by Frankl, Alon and others.

AMS subject classification (1980)

05 C 65 


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Copyright information

© Akadémiai Kiadó 1990

Authors and Affiliations

  • A. Blokhuis
    • 1
  1. 1.Dept. of Mathematics and Comp. Sci.Eindhoven University of TechnologyMB, EindhovenThe Netherlands

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