منابع مشابه
On Disjoint Sets of Differences
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, how...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1997
ISSN: 0012-365X
DOI: 10.1016/s0012-365x(96)00142-2