Let p, q, r be any three lines in the plane passing through a common point and suppose that O, P, Q, R are any four collinear points such that P p, Q q, R r, P and R are harmonic conjugates with respect to O and Q (that is, |OP|/|PQ|=|OR|/|QR|). For every k 2, we construct a set Xn of n = 4k points, which is distributed on the lines p, q, r, but each element of Xn {O} is incident to at most n/2 lines spanned by Xn {O}.
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