Janko group:J2

Definition
This group, denoted $$J_2$$, and also called the Hall-Janko group and sometimes denoted $$HJ$$, is one of the Janko groups. Its existence was conjectured by Janko and it was constructed by Hall and Wales.

The order of the group is:

$$\! 604800 = 2^7 \cdot 3^3 \cdot 5^2 \cdot 7$$

It is one of the member of family::sporadic simple groups.

GAP implementation
GAP does not have an implementation of this group as a group. However, the character table of the group can be accessed as a stored table using GAP's CharacterTable function, if the CtblLib package is loaded:

CharacterTable("J2")