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On conditions guaranteeing that mappings are elements of iteration groups

✍ Scribed by Krzysztof Ciepliński


Publisher
Elsevier Science
Year
2011
Tongue
English
Weight
207 KB
Volume
24
Category
Article
ISSN
0893-9659

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✦ Synopsis


In this note, we prove that if F = {f v : I -→ I, v ∈ V } is a suitable iteration group on an open interval I and a function g : I -→ I is continuous at least at one point and commutes with two mappings f a , f b ∈ F such that b a is irrational, then g ∈ F . If, moreover, f a < id < f b , then the commutativity of g with f a and f b can be replaced by the inequalities

As an application of the obtained results, we give a contribution to Schwaiger's problem concerning iteration groups which are commuting in pairs.