THE PROBLEM OF TIMAN,A.F. ON THE PRECISE ORDER OF DECREASE OF THE BEST APPROXIMATIONS

[摘要] The problem of Timan on finding a necessary and sufficient condition for A(sigma)(f)Lq approximately omega(k)(f, 1/sigma)Lq, sigma --> infinity, is solved. The condition is omega(k)(f; delta)Lq approximately omega(k+1)(f; delta)Lq, delta --> 0. Related problems in other situations have also been studied. (C) 1994 Academic Press, Inc.

[发布日期] 1994-05-01