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The Solution to a Problem of Grünbaum

Published online by Cambridge University Press:  20 November 2018

Peter Salamon
Affiliation:
Department of Mathematical Sciences, San Diego State University, San DiegoCA 92182
Paul Erdös
Affiliation:
Hungarian Academy of Sciences, Budapest, Hungary
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Abstract

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The paper characterizes the set of all possible values for the number of lines determined by n points for n sufficiently large. For the lower bound of Kelly and Moser for the number of lines in a configuration with nk collinear points is shown to be sharp and it is shown that all values between Mmin(k) and Mmax(k) are assumed with the exception of Mmax — 1 and Mmax — 3. Exact expressions are obtained for the lower end of the continuum of values leading down from In particular, the best value of c = 1 is obtained in Erdös’ previous expression for this lower end of the continuum.

Keywords

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1988

References

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