important to be able to generate pseudo-random numbers efficiently, the
generation needs to be reproducible and a PRNG needs to satisfy many usual
statistical properties. Finally, from our point a view, it is essential to prove
-that a PRNG is chaotic. Devaney~\cite{Devaney} proposed a common mathematical
-formulation of chaotic dynamical systems. Concerning the statistical tests,
-TestU01the is the best-known public-domain statistical testing packages. So we
-use it for all our PRNGs, especially the {\it BigCrush} which is based on the largest
-serie of tests.
+that a PRNG is chaotic. Concerning the statistical tests, TestU01 is the
+best-known public-domain statistical testing package. So we use it for all our
+PRNGs, especially the {\it BigCrush} which provides the largest serie of tests.
+Concerning the chaotic properties, Devaney~\cite{Devaney} proposed a common
+mathematical formulation of chaotic dynamical systems.
In a previous work~\cite{bgw09:ip} we have proposed a new familly of chaotic
-PRNG based on chaotic iterations (IC). In this paper we propose a faster
-version which is also proven to be chaotic with the Devaney formulation.
+PRNG based on chaotic iterations (IC). We have proven that these PRNGs are
+chaotic in the Devaney's sense. In this paper we propose a faster version which
+is also proven to be chaotic.
Although graphics processing units (GPU) was initially designed to accelerate
the manipulation of images, they are nowadays commonly used in many scientific
random numbers per seconds on a GeForce 7800 GTX GPU (which is quite old now).
In \cite{ZRKB10}, the authors propose different versions of efficient GPU PRNGs
-based on Lagged Fibonacci, Hybrid Taus or Hybrid Taus. They have used these
-PRNGs for Langevin simulations of biomolecules fully implemented on GPU.
+based on Lagged Fibonacci, Hybrid Taus or Hybrid Taus. They have used these
+PRNGs for Langevin simulations of biomolecules fully implemented on
+GPU. Performance of the GPU versions are far better than those obtained with a
+CPU and these PRNGs succeed to pass the {\it BigCrush} test of TestU01. There is
+no mention that their PRNGs have chaos mathematical properties.
+
+To the best of our knowledge no GPU implementation have been proven to have chaotic properties.
\section{Basic Recalls}
\label{section:BASIC RECALLS}