Maximal Subgroups
Wilson (1999) gave the 30 classes of maximal subgroups of the baby monster as follows:
2.2E6(2):2 This is the centralizer of an involution, and is the subgroup fixing a point of the smallest permutation representation on 13 571 955 000 points.
21+22.Co2
Fi23
29+16.S8(2)
Th
(22 × F4(2)):2
22+10+20.(M22:2 × S3)
.L5(2)
S3 × Fi22:2
.(S5 × L3(2))
HN:2
O8+(3):S4
31+8.21+6.U4(2).2
(32:D8 × U4(3).2.2).2
5:4 × HS:2
S4 × 2F4(2)
.(S4 × 2S4)
S5 × M22:2
(S6 × L3(4):2).2
53.L3(5)
51+4.21+4.A5.4
(S6 × S6).4
52:4S4 × S5
L2(49).23
L2(31)
M11
L3(3)
L2(17):2
L2(11):2
47:23
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