Action of automorphisms



This page provides information about the group of outer automorphisms of G. First we give the order of the group of outer automorphisms, as well as the minimal number of generators. For each generator of this group of outer automorphisms, we choose an automorphism of G representing it, we give the order of the class in the outer automorphism group (which could be higher than the order of the automorphism), a table describing the action of the automorphism on the generators of the group G, and another table describing the map induced by the automorphism in the cohomology ring of the group G.



The group of outer automorphisms of G has order 4
Number of generators: 2






Automorphism number 1
Order of the class of the automorphism in the outer automorphism group: 2


Group generator Image under automorphism
g1 g1 g2
g2 g2 g4
g3 g3
g4 g4


This automorphism induces the identity homomorphism on cohomology




Automorphism number 2
Order of the class of the automorphism in the outer automorphism group: 2


Group generator Image under automorphism
g1 g1 g3
g2 g2 g4
g3 g3
g4 g4


Cohomology generator Image induced by automorphism
z z
y z + y
x x
w w