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{\bf David Bevan}
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{\bf Sets of Points Determining Only Acute Angles and Some Related Colouring Problems}
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We present both probabilistic and constructive lower
bounds on the maximum size of a set of points ${\cal S} \subseteq
{\Bbb R}^d$ such that every angle determined by three points in
${\cal S}$ is acute, considering especially the case ${\cal S}
\subseteq\{0,1\}^d$. These results improve upon a probabilistic
lower bound of Erd\H{o}s and F\"uredi. We also present lower
bounds for some generalisations of the acute angles problem,
considering especially some problems concerning colourings of sets
of integers.
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