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Licensed Unlicensed Requires Authentication Published by De Gruyter May 22, 2015

Complexities of Relational Structures

David Hartman, Jan Hubička and Jaroslav Nešetřil
From the journal Mathematica Slovaca

Abstract

The relational complexity, introduced by G. Cherlin, G. Martin, and D. Saracino, is a measure of ultrahomogeneity of a relational structure. It provides an information on minimal arity of additional invariant relations needed to turn given structure into an ultrahomogeneous one. The original motivation was group theory. This work focuses more on structures and provides an alternative approach. Our study is motivated by related concept of lift complexity studied by Hubička and Nešetřil.

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Received: 2013-5-30
Accepted: 2013-6-6
Published Online: 2015-5-22
Published in Print: 2015-4-1

© Mathematical Institute Slovak Academy of Sciences

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