Random recursive trees: A boundary theory approach

We show that an algorithmic construction of sequences of recursive trees leads to a direct proof of the convergence of random recursive trees in an associated Doob-Martin compactification; it also gives a representation of the limit in terms of the input sequence of the algorithm. We further show that this approach can be used to obtain strong limit theorems for various tree functionals, such as path length or the Wiener index

The Meir-Keeler Fixed Point Theorem for Quasi-Metric Spaces and Some Consequences

[EN] We obtain quasi-metric versions of the famous Meir¿Keeler fixed point theorem from which we deduce quasi-metric generalizations of Boyd¿Wong¿s fixed point theorem. In fact, one of these generalizations provides a solution for a question recently raised in the paper ¿On the fixed point theory in bicomplete quasi-metric spaces¿, J. Nonlinear Sci. Appl. 2016, 9, 5245¿5251. We also give an application to the study of existence of solution for a type of recurrence equations associated to certain nonlinear difference equationsPedro Tirado acknowledges the support of the Ministerio de Ciencia, Innovación y Universidades, under grant PGC2018-095709-B-C21Romaguera Bonilla, S.; Tirado Peláez, P. (2019). The Meir-Keeler Fixed Point Theorem for Quasi-Metric Spaces and Some Consequences. Symmetry (Basel). 11(6):1-10. https://doi.org/10.3390/sym11060741S110116Alegre, C., Dağ, H., Romaguera, S., & Tirado, P. (2016). On the fixed point theory in bicomplete quasi-metric spaces. 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