On Disjoint Sets of Differences
نویسنده
چکیده
must hold, where A(x) denotes the number of elements of A up to x. It is quite natural to ask how much the situation changes if we cut A into two parts, A' and A ", and demand only that no a i' a, should coincide with any a i ' -a,' . This question was proposed by Erdős and Graham in [2], and it seemed likely that no considerable increase can be achieved in the density of A . We shall show, however, that the situation changes dramatically, and we can construct very dense sequences . Let us see first the precise formulation of the problem [2, p . 50] : "Let 99 0022-314X/84 $3 .00
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تاریخ انتشار 1982