Abstract:
For the function $g(n)$ describing the maximal possible growth of the $l_\infty$-norms of maximal cross approximations of an $n \times n$ matrix, the inequality $4g(2k)\leqslant g(7k+3)$ is proved. This inequality implies the bound $g(n) \geqslant Cn^{\log_{7/2}4}$.
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