A recipe for an unpredictable random number generator
  In this work we present a model for computation of random processes in digital computers which solves the problem of periodic sequences and hidden errors produced by correlations. We show that systems with non-invertible non-linearities can produce unpredictable sequences of independent random numbers. We illustrate our result with some numerical calculations related with random walks simulations. 
Monica A. Garcia-Nustes, Leonardo Trujillo and Jorge A. Gonzalez