On the pseudorandomness of quaternary sequences derived from sequences over F_4
In analogy to the corresponding measures of pseudorandomness for quaternary sequences introduced by Mauduit and S\'ark\"ozy (for m-ary sequences) we introduce the well-distribution measure and correlation measure of order k for sequences over F4. Using any fixed bijection from F4 to the set of complex fourth roots of unity, we analyze the relation of these pseudorandomness measures for sequences over F4 and for the corresponding quaternary sequences. More precisely, we show that they differ only by a multiplicative constant (depending only on k). We also apply the results for deriving new quaternary pseudorandom sequences from pseudorandom sequences over F4 and vice versa.
This is joint work with Arne Winterhof.