AAECC (2005) 16: 219–228 DOI 10.1007/s00200-005-0181-0 Alev Topuzo˘ glu · Arne Winterhof On the linear complexity profile of nonlinear congruential pseudorandom number generators of higher orders Received: 7 April 2004 / Published online: 1 July 2005 © Springer-Verlag 2005 Abstract Nonlinear congruential methods are attractive alternatives to the clas- sical linear congruential method for pseudorandom number generation. Genera- tors of higher orders are of interest since they admit longer periods. We obtain lower bounds on the linear complexity profile of nonlinear pseudorandom number generators of higher orders. The results have applications in cryptography and in quasi-Monte Carlo methods. Keywords Linear complexity profile · Nonlinear pseudorandom number gener- ators · Inversive generators · Sequences over finite fields · Recurrences of higher order 1 Introduction The linear complexity profile of a sequence (s n ) = s 0 ,s 1 ,... over the field F is the function L((s n ),N) defined for every positive integer N , as the least order L of a linear recurrence relation over F s n+L = c L-1 s n+L-1 + ... + c 0 s n , 0 n N -L-1, which (s n ) satisfies. We use the convention that L((s n ),N) = 0 if the first N elements of (s n ) are all zero and L((s n ),N) = N if the first N - 1 elements of (s n ) are zero and s N -1 = 0. A. Topuzo˘ glu Sabanci University, Orhanli, 34956 Tuzla, Istanbul, Turkey E-mail: alev@sabanciuniv.edu A. Winterhof (B ) Johann Radon Institute for Computational and Applied Mathematics, Austrian Academy of Sciences, Altenbergerstr. 69, 4040 Linz, Austria E-mail: arne.winterhof@oeaw.ac.at