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Claim. The Theorem and Corollary of W. M. Schmidt, Irregularities of distribution. VI, Compositio Math. 24 (1972), 63–74 (p. 64). For a sequence ξ1,ξ2,…\xi_1,\xi_2,\ldots in the unit interval let Z(n,α)Z(n,\alpha) count the i≤ni\le n with 0≤ξi<α0\le\xi_i<\alpha, let D(n,α)=∣Z(n,α)−nα∣D(n,\alpha)=\lvert Z(n,\alpha)-n\alpha\rvert, and for κ≥0\kappa\ge0 let S(κ)S(\kappa) be the set of α\alpha with D(n,α)≤κD(n,\alpha)\le\kappa for every nn. If d>4κd>4\kappa, then the dd-th derived set of S(κ)S(\kappa) is empty. Hence each S(κ)S(\kappa) is at most countable and nowhere dense, and S(∞)=⋃κS(κ)S(\infty)=\bigcup_\kappa S(\kappa), the set of anchors α\alpha at which D(n,α)D(n,\alpha) stays bounded in nn, is at most countable. So for every sequence all but countably many anchored intervals [0,α)[0,\alpha) have lim sup⁡N∣DN([0,α))∣=∞\limsup_N\lvert D_N([0,\alpha))\rvert=\infty, which answers Problem 255 yes and sharpens the measure-zero statement of part I of the series (Schmidt 1968), which already answers the question. The paper's closing example, a sequence for which the dd-th derived set of S(d)S(d) is nonempty for every dd, shows that 4κ4\kappa cannot be lowered to κ−ε\kappa-\varepsilon. The source card is Schmidt 1972.

Depends on. Nothing in this wiki; the result rests on the cited paper alone.

Dating. The page is dated by the volume's year; the journal record (Compositio Math. 24 (1972), no. 1, 63–74) gives no day, and the day in the page name is a placeholder.

Acceptance. Refereed: Compositio Math. 24 (1972), no. 1, 63–74. Reviewed: the site's curator, T. F. Bloom, labels the problem PROVED (LEAN) and credits this paper in the problem's commentary with the statement that the question holds for all but countably many intervals [0,x][0,x]. The curator is independent of the author.