论文信息 - On the Fixed Point Property for (3 + 1)-Free Ordered Sets

On the Fixed Point Property for (3 + 1)-Free Ordered Sets

We prove that if a finite (3 + 1)-free ordered set of height two has the fixed point property, then it is dismantlable by irreducibles. We provide an example of a finite (3 + 1)-free ordered set of height three with the fixed point property and no irreducible elements. We characterize the minimal automorphic ordered sets which are respectively (3 + 1)-free, (2 + 2)-free and N-free.

Imed Zaguia

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