Alves, João FerreiraSilva, Luis2016-05-112016-05-112015-06ALVES, João Ferreira; SILVA, Luís Manuel Ferreira da - Nonautonomous graphs and topological entropy of nonautonomous Lorenz systems. International Journal of Bifurcation and Chaos. ISSN. 0218-1274. Vol. 25, N.º 6 (2015), pp. 1550079-1-1550079-9.0218-12741793-6551http://hdl.handle.net/10400.21/6184In this work, we associate a p-periodic nonautonomous graph to each p-periodic nonautonomous Lorenz system with finite critical orbits. We develop Perron-Frobenius theory for nonautonomous graphs and use it to calculate their entropy. Finally, we prove that the topological entropy of a p-periodic nonautonomous Lorenz system is equal to the entropy of its associated nonautonomous graph.engNonautonomous dynamical systemsSymbolic dynamicsGraphsEntropyjournal article10.1142/S0218127415500790