Additive Bases without Any Essential Subsets

نویسنده

  • PETER HEGARTY
چکیده

Let A be a basis for N0 of some order. By an essential subset of A one means a subset P such that A\P is no longer a basis (of any order) and such that P is minimal among all subsets of A with this property. In a recent paper, Deschamps and Farhi asked whether every basis of N0 possesses some such subset. We construct, for every integer h ≥ 2, a basis of order h with no essential subsets. We also exhibit bases for Z without essential subsets.

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تاریخ انتشار 2008