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Homework Help: Discrete math problem college level question

  1. Sep 22, 2004 #1
    Suppose 2n people sit on a round table and are shaking hands in
    pairs. Suppose that etiquette is observed and no 2 shakes cross. Let
    S_n be the number of possible shaking hands arrangements of this sort.

    Determine S_10.
  2. jcsd
  3. Sep 23, 2004 #2
    I recommend trying to work this out for n=2, 3, and 4 and then find a pattern.

    You'll need to find a formula for the sum of the first k whole numbers which is probably in your book somewhere.
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