Finished "Twice Shy", by Dick Francis. When a schoolteacher is asked by a friend to help him out with a computer program to predict the winners of horse races, he little thinks his life will be threatened by gangsters out to steal the betting system for themselves. Absolutely excellent - one of the best in the series so far! And fond memories of the days of personal computers whose programs were loaded from cassette tapes (the book was published in 1981). It's even got snippets of BASIC programs in it
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