On the number of q-ary quasi-perfect codes with covering radius 2
In this paper we present a family of q-ary nonlinear quasi-perfect codes with covering radius 2. The codes have length n = q^m and size M = q^n - m - 1 where q is a prime power, q ≥ 3, m is an integer, m ≥ 2. We prove that there are more than q^q^cn nonequivalent such codes of length n, for all sufficiently large n and a constant c = 1/q - ε.
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