Ghost chimneys
نویسندگان
چکیده
A planar point set S is an (i, t) set of ghost chimneys if there exist lines H0, H1, . . . ,Ht−1 such that the orthogonal projection of S onto Hj consists of exactly i + j distinct points. We give upper and lower bounds on the maximum value of t in an (i, t) set of ghost chimneys, showing that it is linear in i.
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