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Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.

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Statement

Theorem 5.4 (p. 9). Let h1,…,hnh_1,\ldots,h_n be positive integers and GG the set of points (y1,…,yn)(y_1,\ldots,y_n) with yi∈Zy_i\in\mathbb Z and 0≤yi≤hi0\le y_i\le h_i. A set of hyperplanes of AG⁡(n,R)\operatorname{AG}(n,\mathbb R) that covers all but one point of GG has at least h1+h2+⋯+hnh_1+h_2+\cdots+h_n members.

The phrase "all but one point" means that exactly one point of GG lies on no hyperplane of the set, as in the case t=1t=1 of Theorem 5.3. The paper attributes the theorem to N. Alon and Z. Füredi, Covering the cube by affine hyperplanes, European J. Combin. 14 (1993), 79–83.

Proof pointer

P. 8: the paper calls it an immediate corollary of Theorem 5.3 with t=1t=1; take Si={0,1,…,hi}S_i=\{0,1,\ldots,h_i\} and DiD_i the coordinate of the uncovered point.

Read depth

Claims checked: the statement was read clause by clause against p. 9 of the print.

Dependencies

Theorem 5.3.

Source. Simeon Ball and Oriol Serra, Punctured combinatorial Nullstellensätze, Combinatorica 29 (2009), 511–522, doi:10.1007/s00493-009-2509-z. Labels and page numbers are those of the corrected author manuscript dated 14 June 2011, the edition named on the source card.

Bears on

None recorded. The paper names no Erdős problem.