Page 21 - Becoming Metric Wise

10 Becoming Metric-Wise

this set may be denoted as: {nAN: n has exactly two divisors, namely
itself and the number 1}. By definition an object either belongs to a
given set or it does not. If it belongs to a set it belongs exactly once to
the set, and it does not matter in which order a set’s members are listed.
Sets are denoted using the following type of brackets {.}. Consequently
the two objects {y,7, }and { , y, 7} denote the same set.