File:Z4latticeofsubgroups.png

This file was created using Graphviz with the following code:

digraph G{
        rankdir = "BT";
        Wholegroup[peripheries=2,label="{e,a,a^2,a^3}; for Z/4Z notation: {0,1,2,3}; whole group"];
        Trivialsubgroup[peripheries=2,label="{e}; for Z/4Z notation: {0}; trivial"];
        Middle[label="{e,a^2}; for Z/4Z notation: {0,2}; cyclic of order 2"];
        Trivialsubgroup -> Middle -> Wholegroup;
}