Long arithmetic progressions in sumsets: Thresholds and bounds
Long arithmetic progressions in sumsets: Thresholds and bounds
复制标题
求和集中的长算术级数:阈值和界限
DOI:
10.1090/s0894-0347-05-00502-3
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发表时间:
2005
影响因子:
3.9
通讯作者:
V. Vu
中科院分区:
文献类型:
--
作者:
E. Szemerédi;V. Vu
l∗A = {a1 + · · ·+ al|ai ∈ Ai, ai = aj}. Among the most well-known results in all of mathematics are Vinogradov’s theorem, which says that 3P (P is the set of primes) contains all sufficiently large odd numbers, and Waring’s conjecture (proved by Hilbert, Hardy and Littlewood, Hua, and many others), which asserts that for any given r, there is a number l such that l∗Nr (N denotes the set of rth powers) contains all sufficiently large positive integers (see [29] for an excellent exposition concerning these results). In recent years, a considerable amount of attention has been paid to the study of finite sumsets. Given a finite set A and a positive integer l, the natural analogue of Vinogadov-Waring results is to show that under proper conditions, the sumset lA (l∗A) contains a long arithmetic progression. Let us assume that A is a subset of the interval [n] = {1, . . . , n}, where n is a large positive integer. The concrete problem we would like to address is to estimate the minimum length of the longest arithmetic progression in lA (l∗A) as a function of l, n, and |A|. We denote this function by f(|A|, l, n) (f∗(|A|, l, n)), following the notation in [13]. Many estimates for f(|A|, l, n) have been discovered by Bourgain, Freiman, Halberstam, Green, Ruzsa, and Sarkozy (see Section 3), but most of these results focus on sets with very high density, namely |A| is close to n. Estimating f∗(|A|, l, n) seems much harder, and not much was known prior to our study.