Let R be the relation on the set of people with doctorates
Chapter 8, Problem 8.1.37(choose chapter or problem)
Let R be the relation on the set of people with doctorates such that (a, b) E R if and only if a was the thesis advisor of b. When is an ordered pair (a, b) in R 2 ? When is an ordered pair (a, b) in R n , when n is a positive integer? (Note that every person with a doctorate has a thesis advisor.)
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