Siberian Mathematical Journal

, Volume 47, Issue 2, pp 239–244 | Cite as

The property O n for finite seminormal functors

  • A. V. Ivanov
  • K. V. Matyushichev


We give a finite combinatorial test for finite seminormal functors to possess the property On and use it in establishing that in some cases this property leads to some well-known functors. For example, if some functor F possesses the property O2 then F2 coincides with either exp2 or the squaring functor. Hence we conclude that if F(Dω1) and Dω1 are homeomorphic then F2 is either exp2 or (·)2.


compact space open mapping seminormal functor finite functor exponential functor infinite-to-one mapping 


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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • A. V. Ivanov
    • 1
  • K. V. Matyushichev
    • 1
  1. 1.Petrozavodsk State UniversityPetrozavodskRussia

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