Prüfer p-Group
Prüfer p-Group
The Prüfer -group for a prime number consists of all roots of unity of order , ; that is, . The group, named after the mathematician Heinz Prüfer, is also known as the quasicyclic -group. is an example of a countable -group that is not the direct sum of groups of rank 1. The radii of the circles or disks for each element on the group in the plot decrease with .
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