The 2-Adic Complexity of Ding-Helleseth Generalized Cyclotomic Sequences of Order 2 and Period pq

This paper considers the 2-adic complexity of Ding-Helleseth generalized cyclotomic sequences of order 2 and period pq , where p and q are distinct odd primes with \mathrm {gcd}(p-1,q-1)=2,p\equiv q\equiv 3\pmod 4 . These sequences have been proved to possess good linear complexity. Our results show that the 2-adic complexity of these sequences is at least pq-q-1 . Then it is large enough to resist the attack of the rational approximation algorithm.