  We study the multiplicativity of the output 2-norm for depolarized
Werner-Holevo channels and show that multiplicativity holds for a product of
two identical channels in this class. Moreover, it shown that the depolarized
Werner-Holevo channels do not satisfy the entrywise positivity condition
introduced by C. King and M.B. Ruskai, which suggests that the main result is
non-trivial.
