I am working on one example from Munkres book "Topology"and I would like to clarify one question.
Example: Consider the set [0,1) of real numbers and the set Z+ of positive integers, both in their usual orders; give Z+×[0,1) the dictionary order. This set has the same order type as the set of nonnegative reals; the function f(n×t)=n+t−1
is the required bijective order-preserving correspondence. On the other hand, the set [0,1)×Z+ in the dictionary order has quite a different order type; for example, every element of this ordered set has an immediate successor.
My questions:
1) I've checked that [0,1)×Z+ has the same order type as the set of nonnegative reals, right?
2) Any element (t,n) from [0,1)×Z+ has immediate successor, namely (t,n+1). Right?
3) But elements in Z+×[0,1) have not immediate successors, right?
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