On the 4-adic complexity of the two-prime quaternary generator

R. Hofer and A. Winterhof proved that the 2-adic complexity of two-prime (binary) generator period pq with two odd primes $$p\ne q$$ is close to its it can attain maximum in many cases. When applied producing quaternary sequences, we need determine 4-adic complexity. It there are only possible values for generator, which at least $$pq-1-\max \{\log _4(pq^2),\log _4(p^2q)\}$$ . Examples p q $$5\le p, <10000$$ illustrate takes one value larger than $$pq-\max _4(p),\log _4(q)\}$$ , period. So good enough resist attack rational approximation algorithm.