10th Joint Conf. on Math. and Comp. Sci., May 22–25, 2014, Cluj, Romania 1 Pseudorandomness of binary threshold sequences derived from multiplicative inverse László Mérai Department of Computer Algebra, Eötvös Loránd University, Budapest, Hungary merai@cs.elte.hu Let p be a prime and c1 , c2 , . . . , ch ∈ Zp be fixed elements. For initial values x1 , . . . , xh ∈ Zp consider the sequence (xn ) defined by the linear recursion xn = c1 xn−1 + . . . + ch xn−h , n > h. The aim of the talk is to study the pseudorandom properties of the following finite binary sequence ET = {e1 , e2 , . . . , eT } ∈ {1, −1}T built from the linear recursive sequence (xn ) by the rule 1 if p - f (xn ) and 0 < f −1 (xn ) < p/2 en = -1 otherwise, where f −1 (xn ) is the multiplicative inverse of f (xn ) modulo p.