On the Reducibility of Exact Covering Systems
نویسنده
چکیده
There exist irreducible exact covering systems (ECS). These are ECS which are not a proper split of a coarser ECS. However, an ECS admiting a maximal modulus which is divisible by at most two distinct primes, primely splits a coarser ECS. As a consequence, if all moduli of an ECS A are divisible by at most two distinct primes, then A is natural. That is, A can be formed by iteratively splitting the trivial ECS.
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