Semi-Inner Products and Parapreseminorms on Groups and a Generalization of a Theorem of Maksa and Volkmann on Additive Functions

  • Árpád SzázEmail author


By using inner products and paraprenorms on groups, we prove a natural generalization of a basic theorem of Gyula Maksa and Peter Volkmann on additive functions.


Groups Semi-inner products Parapreseminorms Additive functions 

Mathematics Subject Classification (2010)

Primary 39B52 39B62; Secondary 20A99 46C50 



The work of the author has been supported by the Hungarian Scientific Research Fund (OTKA) Grant K-111651.

Moreover, the author is greatly indebted to Zoltán Boros, Gyula Maksa, Attila Gilányi and Jens Schwaiger for some inspiring conversations.


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Authors and Affiliations

  1. 1.Department of MathematicsUniversity of DebrecenDebrecenHungary

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