A Characterization of Covering Equivalence
نویسنده
چکیده
Abstract. Let A = {as(mod ns)}ks=1 and B = {bt(mod mt)} l t=1 be two systems of residue classes. If |{1 6 s 6 k : x ≡ as (mod ns)}| and |{1 6 t 6 l : x ≡ bt (mod mt)}| are equal for all x ∈ Z, then A and B are said to be covering equivalent. In this paper we characterize the covering equivalence in a simple and new way. Using the characterization we partially confirm a conjecture of R. L. Graham and K. O’Bryant.
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تاریخ انتشار 2004