ATLAS: Non­split extension 24.A8 = 24.L4(2)

Order = 322560 =
Mult = 2.
Out = 1.
The page for the image A8 = L4(2) is available here.

The following information is available for 24.A8:

Standard generators

Standard generators of 24.A8 are a and b where a is in class 3A, b has order 7, ab has order 6, [a, b] has order 2 and abab2ab5 has order 6. An equivalent condition to [a, b] having order 2 is that abbb has order 12. These generators map onto standard generators of A8.
Standard generators of the double cover 24.2A8 are preimages A and B where A has order 3 and B has order 7. These generators map onto standard generators of 2A8.

NB: Class 3A is the class of elements of order 3 with centraliser 3 × A5, and maps onto Class 3A of A8.


A presentation of 24.A8 on its standard generators is given below.

< a, b | a3 = b7 = (ab)6 = [a, b]2 = abab2a-1bab-2ab3ab-3ab-3 = 1 >.

This presentation is available in Magma format as follows: 24A8 on a and b.


The representations of 24.A8 available are:
Main ATLAS page Go to main ATLAS (version 2.0) page.
Miscellaneous groups page Go to miscellaneous groups page.
Old 24A8 page There is no old 24A8 page (not even on the A8 page) in the ATLAS version 1.
ftp access Anonymous ftp access is also available on

Version 2.0 created on 24th July 1999.
Last updated 24.07.99 by JNB.
Information checked to Level 0 on 24.07.99 by JNB.
R.A.Wilson, R.A.Parker and J.N.Bray.