ON A GENERALIZATION OF SZEMERÉDI'S THEOREM 1
AbstractLet $N$ be a natural number and $A \subseteq [1, \dots, N]^2$ be a set of cardinality at least $N^2 / (\log \log N)^c$, where $c > 0$ is an absolute constant. We prove that $A$ contains a triple $\{(k, m), (k+d, m), (k, m+d) \}$, where $d > 0$. This theorem is a two-dimensional generalization of Szemerédi's theorem on arithmetic progressions. (Published Online October 13 2006)(Received May 15 2005) (Revised January 10 2006) Maths Classification 35J25; 37A15. Footnotes1 This work was supported by the program ‘Leading Scientific Schools’ (project no. 136.2003.1), and by RFFI grant no. 02-01-00912 and INTAS (grant no. 03-51-5-70). |