✦ LIBER ✦

On illuminating line segments in the plane

✍ Scribed by Jurek Czyzowicz; Eduardo Rivera-Campo; Jorge Urrutia; Joseph Zaks

Publisher: Elsevier Science
Year: 1995
Tongue: English
Weight: 269 KB
Volume: 137
Category: Article
ISSN: 0012-365X
DOI: 10.1016/0012-365x(93)e0127-p

No coin nor oath required. For personal study only.

✦ Synopsis

Let F be a family of n convex sets in the plane. A set of light sources S illuminates F if every point on the boundary of each element of F is visible from at least one element in S. We prove that if F is a family of n line segments, n >/11, then [-2n/3 7 light sources are always sufficient to illuminate F. If all the elements in F are parallel to the x or the y-axes, then F can be illuminated by at most [-(n + 1)/2 7 light sources.

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