Essentialities in Additive Bases
نویسنده
چکیده
Let A be an asymptotic basis for N0 of some order. By an essentiality of A one means a subset P such that A\P is no longer an asymptotic basis of any order and such that P is minimal among all subsets of A with this property. A finite essentiality of A is called an essential subset. In a recent paper, Deschamps and Farhi asked the following two questions : (i) does every asymptotic basis of N0 possess some essentiality ? (ii) is the number of essential subsets of size at most k of an asymptotic basis of order h bounded by a function of k and h only (they showed the number is always finite) ? We answer the latter question in the affirmative, and the former in the negative by means of an explicit construction, for every integer h ≥ 2, of an asymptotic basis of order h with no essentialities.
منابع مشابه
Additive Bases without Any Essentialities
Let A be a basis for N0 of some order. By an essentiality 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 essentialities.
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