Proportions of Sidon Sets Are I0 Subsets
نویسندگان
چکیده
It is proved that proportions of Sidon sets are I0 subsets of controlled degree. That is, a set E is Sidon if and only if, there are r > 0 and positive integer n such that, for every finite subset F ⊂ E, there is H ⊂ F with the cardinality of H at least r times the cardinality of F and N(H) ≤ n (N(H) is a measure of the degree of being I0). This paper leaves open David Grow’s question of whether Sidon sets are finite unions of I0 sets.
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