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Multiple blocking sets and arcs in finite planes
Simeon Ball, Multiple blocking sets and arcs in finite planes, Journal of the London Mathematical Society 54 (1996), 581–593, DOI 10.1112/jlms/54.3.581.
The edition read is the undated, eighteen-page author manuscript, accessed 2026-10-16. Its page numbers differ from the journal edition. The author's bibliography warns that the manuscripts can differ from their published versions; no page-by-page equivalence is asserted here.
The abstract describes lower bounds on the size of multiple blocking sets in Desarguesian planes, stronger bounds over prime fields, and applications to arcs in small planes. The introduction defines the minimum-intersection condition for a multiple blocking set and relates it to the upper bound on intersections for the complementary arc.
Bears on. This source provides terminology and a prospective source of size bounds for Problem 1159's bounded line-intersection question. No theorem from this source is used here to settle that question. Reading covers the abstract and introductory definitions; no proof is verified on this card.
No file of this source is held: no license on record permits its redistribution. The manuscript and the author's bibliography state no license or usage notice in the material read on 2026-10-16, so the term is unstated.