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**Z** is infinite but it is countable because we can define

i.e.,

f:N->^{bijective}Zf(x) :=ifxis eventhen-x/2else(x+1)/2

f= [0, 1, -1, 2, -2, 3, -3, ...].

*While Z is infinite, we can enumerate all its elements.*

Author: Wolfgang Schreiner

Last Modification: December 7, 1999