  We determine the 2-adic complexity of the Ding-Helleseth-Martinsen (DHM)
binary sequences by using cyclotomic numbers of order four, "Gauss periods" and
"quadratic Gauss sum" on finite field $\mathbb{F}_q$ and valued in
$\mathbb{Z}_{2^N-1}$ where $q \equiv 5\pmod 8$ is a prime number and $N=2q$ is
the period of the DHM sequences.
