List of finite simple groups

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In mathematics, the classification of finite simple groups states that every finite simple group is cyclic, or alternating, or in one of 16 families of groups of Lie type, or one of 26 sporadic groups.

Contents

The list below gives all finite simple groups, together with their order, the size of the Schur multiplier, the size of the outer automorphism group, usually some small representations, and lists of all duplicates.

Summary

The following table is a complete list of the 18 families of finite simple groups and the 26 sporadic simple groups, along with their orders. Any non-simple members of each family are listed, as well as any members duplicated within a family or between families. (In removing duplicates it is useful to note that no two finite simple groups have the same order, except that the group A8 = A3(2) and A2(4) both have order 20160, and that the group Bn(q) has the same order as Cn(q) for q odd, n > 2. The smallest of the latter pairs of groups are B3(3) and C3(3) which both have order 4585351680.)

There is an unfortunate conflict between the notations for the alternating groups An and the groups of Lie type An(q). Some authors use various different fonts for An to distinguish them. In particular, in this article we make the distinction by setting the alternating groups An in Roman font and the Lie-type groups An(q) in italic.

In what follows, n is a positive integer, and q is a positive power of a prime number p, with the restrictions noted. The notation (a,b) represents the greatest common divisor of the integers a and b.

ClassFamilyOrderExclusionsDuplicates
Cyclic groups Zpp primeNoneNone
Alternating groups An
n > 4
None
  • A5A1(4) ≃ A1(5)
  • A6A1(9)
  • A8A3(2)
Classical Chevalley groups An(q)A1(2), A1(3)
  • A1(4) ≃ A1(5) ≃ A5
  • A1(7) ≃ A2(2)
  • A1(9) ≃ A6
  • A3(2) ≃ A8
Bn(q)
n > 1
B2(2)
  • Bn(2m) ≃ Cn(2m)
  • B2(3) ≃ 2A3(22)
Cn(q)
n > 2
NoneCn(2m) ≃ Bn(2m)
Dn(q)
n > 3
NoneNone
Exceptional Chevalley groups E6(q)NoneNone
E7(q)NoneNone
E8(q)NoneNone
F4(q)NoneNone
G2(q)G2(2)None
Classical Steinberg groups 2An(q2)
n > 1
2A2(22)2A3(22) ≃ B2(3)
2Dn(q2)
n > 3
NoneNone
Exceptional Steinberg groups 2E6(q2)NoneNone
3D4(q3)NoneNone
Suzuki groups 2B2(q)
q = 22n+1
NoneNone
Ree groups
+ Tits group
2F4(q)
q = 22n+1
NoneNone
2F4(2)′212(26 + 1)(24 − 1)(23 + 1)(2 − 1)/2 = 17971200
2G2(q)
q = 32n+1
NoneNone
Mathieu groups M117920
M1295040
M22443520
M2310200960
M24244823040
Janko groups J1175560
J2604800
J350232960
J486775571046077562880
Conway groups Co3495766656000
Co242305421312000
Co14157776806543360000
Fischer groups Fi2264561751654400
Fi234089470473293004800
Fi241255205709190661721292800
Higman–Sims group HS44352000
McLaughlin group McL898128000
Held group He4030387200
Rudvalis group Ru145926144000
Suzuki sporadic group Suz448345497600
O'Nan group O'N460815505920
Harada–Norton group HN273030912000000
Lyons group Ly51765179004000000
Thompson group Th90745943887872000
Baby Monster group B4154781481226426191177580544000000
Monster group M808017424794512875886459904961710757005754368000000000

Cyclic groups, Zp

Simplicity: Simple for p a prime number.

Order:p

Schur multiplier: Trivial.

Outer automorphism group: Cyclic of order p  1.

Other names: Z/pZ, Cp

Remarks: These are the only simple groups that are not perfect.

Alternating groups, An, n > 4

Simplicity: Solvable for n ≤ 4, otherwise simple.

Order:n!/2 when n > 1.

Schur multiplier: 2 for n = 5 or n > 7, 6 for n = 6 or 7; see Covering groups of the alternating and symmetric groups

Outer automorphism group: In general 2. Exceptions: for n = 1, n = 2, it is trivial, and for n = 6, it has order 4 (elementary abelian).

Other names: Altn.

Isomorphisms: A1 and A2 are trivial. A3 is cyclic of order 3. A4 is isomorphic to A1(3) (solvable). A5 is isomorphic to A1(4) and to A1(5). A6 is isomorphic to A1(9) and to the derived group B2(2)′. A8 is isomorphic to A3(2).

Remarks: An index 2 subgroup of the symmetric group of permutations of n points when n > 1.

Groups of Lie type

Notation:n is a positive integer, q > 1 is a power of a prime number p, and is the order of some underlying finite field. The order of the outer automorphism group is written as dfg, where d is the order of the group of "diagonal automorphisms", f is the order of the (cyclic) group of "field automorphisms" (generated by a Frobenius automorphism), and g is the order of the group of "graph automorphisms" (coming from automorphisms of the Dynkin diagram). The outer automorphism group is often, but not always, isomorphic to the semidirect product where all these groups are cyclic of the respective orders d, f, g, except for type , odd, where the group of order is , and (only when ) , the symmetric group on three elements. The notation (a,b) represents the greatest common divisor of the integers a and b.

Chevalley groups, An(q), Bn(q) n > 1, Cn(q) n > 2, Dn(q) n > 3

Chevalley groups, An(q)
linear groups
Chevalley groups, Bn(q) n > 1
orthogonal groups
Chevalley groups, Cn(q) n > 2
symplectic groups
Chevalley groups, Dn(q) n > 3
orthogonal groups
SimplicityA1(2) and A1(3) are solvable, the others are simple.B2(2) is not simple but its derived group B2(2)′ is a simple subgroup of index 2; the others are simple.All simpleAll simple
Order
Schur multiplierFor the simple groups it is cyclic of order (n+1,q−1) except for A1(4) (order 2), A1(9) (order 6), A2(2) (order 2), A2(4) (order 48, product of cyclic groups of orders 3, 4, 4), A3(2) (order 2).(2,q−1) except for B2(2) = S6 (order 2 for B2(2), order 6 for B2(2)′) and B3(2) (order 2) and B3(3) (order 6).(2,q−1) except for C3(2) (order 2).The order is (4,qn−1) (cyclic for n odd, elementary abelian for n even) except for D4(2) (order 4, elementary abelian).
Outer automorphism group(2,q−1)⋅f⋅1 for n = 1; (n+1,q−1)⋅f⋅2 for n > 1, where q = pf(2,q−1)⋅f⋅1 for q odd or n > 2; (2,q−1)⋅f⋅2 for q even and n = 2, where q = pf(2,q−1)⋅f⋅1, where q = pf(2,q−1)2fS3 for n = 4, (2,q−1)2f⋅2 for n > 4 even, (4,qn−1)⋅f⋅2 for n odd, where q = pf, and S3 is the symmetric group of order 3! on 3 points.
Other names Projective special linear groups, PSLn+1(q), Ln+1(q), PSL(n + 1,q)O2n+1(q), Ω2n+1(q) (for q odd).Projective symplectic group, PSp2n(q), PSpn(q) (not recommended), S2n(q), Abelian group (archaic).O2n+(q), PΩ2n+(q). "Hypoabelian group" is an archaic name for this group in characteristic 2.
IsomorphismsA1(2) is isomorphic to the symmetric group on 3 points of order 6. A1(3) is isomorphic to the alternating group A4 (solvable). A1(4) and A1(5) are both isomorphic to the alternating group A5. A1(7) and A2(2) are isomorphic. A1(8) is isomorphic to the derived group 2G2(3)′. A1(9) is isomorphic to A6 and to the derived group B2(2)′. A3(2) is isomorphic to A8.Bn(2m) is isomorphic to Cn(2m). B2(2) is isomorphic to the symmetric group on 6 points, and the derived group B2(2)′ is isomorphic to A1(9) and to A6. B2(3) is isomorphic to 2A3(22).Cn(2m) is isomorphic to Bn(2m)
RemarksThese groups are obtained from the general linear groups GLn+1(q) by taking the elements of determinant 1 (giving the special linear groups SLn+1(q)) and then quotienting out by the center.This is the group obtained from the orthogonal group in dimension 2n + 1 by taking the kernel of the determinant and spinor norm maps. B1(q) also exists, but is the same as A1(q). B2(q) has a non-trivial graph automorphism when q is a power of 2.This group is obtained from the symplectic group in 2n dimensions by quotienting out the center. C1(q) also exists, but is the same as A1(q). C2(q) also exists, but is the same as B2(q).This is the group obtained from the split orthogonal group in dimension 2n by taking the kernel of the determinant (or Dickson invariant in characteristic 2) and spinor norm maps and then killing the center. The groups of type D4 have an unusually large diagram automorphism group of order 6, containing the triality automorphism. D2(q) also exists, but is the same as A1(qA1(q). D3(q) also exists, but is the same as A3(q).

Chevalley groups, E6(q), E7(q), E8(q), F4(q), G2(q)

Chevalley groups, E6(q) Chevalley groups, E7(q) Chevalley groups, E8(q) Chevalley groups, F4(q) Chevalley groups, G2(q)
SimplicityAll simpleAll simpleAll simpleAll simpleG2(2) is not simple but its derived group G2(2)′ is a simple subgroup of index 2; the others are simple.
Orderq36(q12−1)(q9−1)(q8−1)(q6−1)(q5−1)(q2−1)/(3,q−1)q63(q18−1)(q14−1)(q12−1)(q10−1)(q8−1)(q6−1)(q2−1)/(2,q−1)q120(q30−1)(q24−1)(q20−1)(q18−1)(q14−1)(q12−1)(q8−1)(q2−1)q24(q12−1)(q8−1)(q6−1)(q2−1)q6(q6−1)(q2−1)
Schur multiplier(3,q−1)(2,q−1)TrivialTrivial except for F4(2) (order 2)Trivial for the simple groups except for G2(3) (order 3) and G2(4) (order 2)
Outer automorphism group(3,q−1)⋅f⋅2, where q = pf(2,q−1)⋅f⋅1, where q = pf1⋅f⋅1, where q = pf1⋅f⋅1 for q odd, 1⋅f⋅2 for q even, where q = pf1⋅f⋅1 for q not a power of 3, 1⋅f⋅2 for q a power of 3, where q = pf
Other namesExceptional Chevalley groupExceptional Chevalley groupExceptional Chevalley groupExceptional Chevalley groupExceptional Chevalley group
IsomorphismsThe derived group G2(2)′ is isomorphic to 2A2(32).
RemarksHas two representations of dimension 27, and acts on the Lie algebra of dimension 78.Has a representations of dimension 56, and acts on the corresponding Lie algebra of dimension 133.It acts on the corresponding Lie algebra of dimension 248. E8(3) contains the Thompson simple group.These groups act on 27-dimensional exceptional Jordan algebras, which gives them 26-dimensional representations. They also act on the corresponding Lie algebras of dimension 52. F4(q) has a non-trivial graph automorphism when q is a power of 2.These groups are the automorphism groups of 8-dimensional Cayley algebras over finite fields, which gives them 7-dimensional representations. They also act on the corresponding Lie algebras of dimension 14. G2(q) has a non-trivial graph automorphism when q is a power of 3. Moreover, they appear as automorphism groups of certain point-line geometries called split Cayley generalized hexagons.

Steinberg groups, 2An(q2) n > 1, 2Dn(q2) n > 3, 2E6(q2), 3D4(q3)

Steinberg groups, 2An(q2) n > 1
unitary groups
Steinberg groups, 2Dn(q2) n > 3
orthogonal groups
Steinberg groups, 2E6(q2) Steinberg groups, 3D4(q3)
Simplicity2A2(22) is solvable, the others are simple.All simpleAll simpleAll simple
Orderq36(q12−1)(q9+1)(q8−1)(q6−1)(q5+1)(q2−1)/(3,q+1)q12(q8+q4+1)(q6−1)(q2−1)
Schur multiplierCyclic of order (n+1,q+1) for the simple groups, except for 2A3(22) (order 2), 2A3(32) (order 36, product of cyclic groups of orders 3,3,4), 2A5(22) (order 12, product of cyclic groups of orders 2,2,3)Cyclic of order (4,qn+1)(3,q+1) except for 2E6(22) (order 12, product of cyclic groups of orders 2,2,3).Trivial
Outer automorphism group(n+1,q+1)⋅f⋅1, where q2 = pf(4,qn+1)⋅f⋅1, where q2 = pf(3,q+1)⋅f⋅1, where q2 = pf1⋅f⋅1, where q3 = pf
Other namesTwisted Chevalley group, projective special unitary group, PSUn+1(q), PSU(n + 1, q), Un+1(q), 2An(q), 2An(q, q2)2Dn(q), O2n(q), PΩ2n(q), twisted Chevalley group. "Hypoabelian group" is an archaic name for this group in characteristic 2.2E6(q), twisted Chevalley group3D4(q), D42(q3), Twisted Chevalley groups
IsomorphismsThe solvable group 2A2(22) is isomorphic to an extension of the order 8 quaternion group by an elementary abelian group of order 9. 2A2(32) is isomorphic to the derived group G2(2)′. 2A3(22) is isomorphic to B2(3).
RemarksThis is obtained from the unitary group in n + 1 dimensions by taking the subgroup of elements of determinant 1 and then quotienting out by the center.This is the group obtained from the non-split orthogonal group in dimension 2n by taking the kernel of the determinant (or Dickson invariant in characteristic 2) and spinor norm maps and then killing the center. 2D2(q2) also exists, but is the same as A1(q2). 2D3(q2) also exists, but is the same as 2A3(q2).One of the exceptional double covers of 2E6(22) is a subgroup of the baby monster group, and the exceptional central extension by the elementary abelian group of order 4 is a subgroup of the monster group.3D4(23) acts on the unique even 26-dimensional lattice of determinant 3 with no roots.

Suzuki groups, 2B2(22n+1)

Simplicity: Simple for n ≥ 1. The group 2B2(2) is solvable.

Order:q2 (q2 + 1) (q  1), where q = 22n+1.

Schur multiplier: Trivial for n ≠ 1, elementary abelian of order 4 for 2B2(8).

Outer automorphism group:

1⋅f⋅1,

where f = 2n + 1.

Other names: Suz(22n+1), Sz(22n+1).

Isomorphisms:2B2(2) is the Frobenius group of order 20.

Remarks: Suzuki group are Zassenhaus groups acting on sets of size (22n+1)2 + 1, and have 4-dimensional representations over the field with 22n+1 elements. They are the only non-cyclic simple groups whose order is not divisible by 3. They are not related to the sporadic Suzuki group.

Ree groups and Tits group, 2F4(22n+1)

Simplicity: Simple for n  1. The derived group 2F4(2)′ is simple of index 2 in 2F4(2), and is called the Tits group, named for the Belgian mathematician Jacques Tits.

Order:q12 (q6 + 1) (q4  1) (q3 + 1) (q  1), where q = 22n+1.

The Tits group has order 17971200 = 211 ⋅ 33 ⋅ 52 ⋅ 13.

Schur multiplier: Trivial for n  1 and for the Tits group.

Outer automorphism group:

1⋅f⋅1,

where f = 2n + 1. Order 2 for the Tits group.

Remarks: Unlike the other simple groups of Lie type, the Tits group does not have a BN pair, though its automorphism group does so most authors count it as a sort of honorary group of Lie type.

Ree groups, 2G2(32n+1)

Simplicity: Simple for n  1. The group 2G2(3) is not simple, but its derived group 2G2(3)′ is a simple subgroup of index 3.

Order:q3 (q3 + 1) (q  1), where q = 32n+1

Schur multiplier: Trivial for n  1 and for 2G2(3)′.

Outer automorphism group:

1⋅f⋅1,

where f = 2n + 1.

Other names: Ree(32n+1), R(32n+1), E2(32n+1) .

Isomorphisms: The derived group 2G2(3)′ is isomorphic to A1(8).

Remarks:2G2(32n+1) has a doubly transitive permutation representation on 33(2n+1) + 1 points and acts on a 7-dimensional vector space over the field with 32n+1 elements.

Sporadic groups

Mathieu groups, M11, M12, M22, M23, M24

Mathieu group, M11 Mathieu group, M12 Mathieu group, M22 Mathieu group, M23 Mathieu group, M24
Order24 ⋅ 32 ⋅ 5 ⋅ 11 = 792026 ⋅ 33 ⋅ 5 ⋅ 11 = 9504027 ⋅ 32 ⋅ 5 ⋅ 7 ⋅ 11 = 44352027 ⋅ 32 ⋅ 5 ⋅ 7 ⋅ 11 ⋅ 23 = 10200960210 ⋅ 33 ⋅ 5 ⋅ 7 ⋅ 11 ⋅ 23 = 244823040
Schur multiplierTrivialOrder 2Cyclic of order 12 [lower-alpha 1] TrivialTrivial
Outer automorphism groupTrivialOrder 2Order 2TrivialTrivial
RemarksA 4-transitive permutation group on 11 points, and is the point stabilizer of M12 (in the 5-transitive 12-point permutation representation of M12). The group M11 is also contained in M23. The subgroup of M11 fixing a point in the 4-transitive 11-point permutation representation is sometimes called M10, and has a subgroup of index 2 isomorphic to the alternating group A6.A 5-transitive permutation group on 12 points, contained in M24.A 3-transitive permutation group on 22 points, and is the point stabilizer of M23 (in the 4-transitive 23-point permutation representation of M23). The subgroup of M22 fixing a point in the 3-transitive 22-point permutation representation is sometimes called M21, and is isomorphic to PSL(3,4) (i.e. isomorphic to A2(4)).A 4-transitive permutation group on 23 points, and is the point stabilizer of M24 (in the 5-transitive 24-point permutation representation of M24).A 5-transitive permutation group on 24 points.

Janko groups, J1, J2, J3, J4

Janko group, J1 Janko group, J2 Janko group, J3 Janko group, J4
Order23 ⋅ 3 ⋅ 5 ⋅ 7 ⋅ 11 ⋅ 19 = 17556027 ⋅ 33 ⋅ 52 ⋅ 7 = 60480027 ⋅ 35 ⋅ 5 ⋅ 17 ⋅ 19 = 50232960221 ⋅ 33 ⋅ 5 ⋅ 7 ⋅ 113 ⋅ 23 ⋅ 29 ⋅ 31 ⋅ 37 ⋅ 43 = 86775571046077562880
Schur multiplierTrivialOrder 2Order 3Trivial
Outer automorphism groupTrivialOrder 2Order 2Trivial
Other namesJ(1), J(11)Hall–Janko group, HJHigman–Janko–McKay group, HJM
RemarksIt is a subgroup of G2(11), and so has a 7-dimensional representation over the field with 11 elements.The automorphism group J2:2 of J2 is the automorphism group of a rank 3 graph on 100 points called the Hall-Janko graph. It is also the automorphism group of a regular near octagon called the Hall-Janko near octagon. The group J2 is contained in G2(4).J3 seems unrelated to any other sporadic groups (or to anything else). Its triple cover has a 9-dimensional unitary representation over the field with 4 elements.Has a 112-dimensional representation over the field with 2 elements.

Conway groups, Co1, Co2, Co3

Conway group, Co1 Conway group, Co2 Conway group, Co3
Order221 ⋅ 39 ⋅ 54 ⋅ 72 ⋅ 11 ⋅ 13 ⋅ 23 = 4157776806543360000218 ⋅ 36 ⋅ 53 ⋅ 7 ⋅ 11 ⋅ 23 = 42305421312000210 ⋅ 37 ⋅ 53 ⋅ 7 ⋅ 11 ⋅ 23 = 495766656000
Schur multiplierOrder 2TrivialTrivial
Outer automorphism groupTrivialTrivialTrivial
Other names·1·2·3, C3
RemarksThe perfect double cover Co0 of Co1 is the automorphism group of the Leech lattice, and is sometimes denoted by ·0.Subgroup of Co0; fixes a norm 4 vector in the Leech lattice.Subgroup of Co0; fixes a norm 6 vector in the Leech lattice. It has a doubly transitive permutation representation on 276 points.

Fischer groups, Fi22, Fi23, Fi24

Fischer group, Fi22 Fischer group, Fi23 Fischer group, Fi24
Order217 ⋅ 39 ⋅ 52 ⋅ 7 ⋅ 11 ⋅ 13 = 64561751654400218 ⋅ 313 ⋅ 52 ⋅ 7 ⋅ 11 ⋅ 13 ⋅ 17 ⋅ 23 = 4089470473293004800221 ⋅ 316 ⋅ 52 ⋅ 73 ⋅ 11 ⋅ 13 ⋅ 17 ⋅ 23 ⋅ 29 = 1255205709190661721292800
Schur multiplierOrder 6TrivialOrder 3
Outer automorphism groupOrder 2TrivialOrder 2
Other namesM(22)M(23)M(24)′, F3+
RemarksA 3-transposition group whose double cover is contained in Fi23.A 3-transposition group contained in Fi24′.The triple cover is contained in the monster group.

Higman–Sims group, HS

Order: 29 ⋅ 32 ⋅ 53 ⋅ 7 ⋅ 11 = 44352000

Schur multiplier: Order 2.

Outer automorphism group: Order 2.

Remarks: It acts as a rank 3 permutation group on the Higman Sims graph with 100 points, and is contained in Co2 and in Co3.

McLaughlin group, McL

Order: 27 ⋅ 36 ⋅ 53 ⋅ 7 ⋅ 11 = 898128000

Schur multiplier: Order 3.

Outer automorphism group: Order 2.

Remarks: Acts as a rank 3 permutation group on the McLaughlin graph with 275 points, and is contained in Co2 and in Co3.

Held group, He

Order: 210 ⋅ 33 ⋅ 52 ⋅ 73 ⋅ 17 = 4030387200

Schur multiplier: Trivial.

Outer automorphism group: Order 2.

Other names: Held–Higman–McKay group, HHM, F7, HTH

Remarks: Centralizes an element of order 7 in the monster group.

Rudvalis group, Ru

Order: 214 ⋅ 33 ⋅ 53 ⋅ 7 ⋅ 13 ⋅ 29 = 145926144000

Schur multiplier: Order 2.

Outer automorphism group: Trivial.

Remarks: The double cover acts on a 28-dimensional lattice over the Gaussian integers.

Suzuki sporadic group, Suz

Order: 213 ⋅ 37 ⋅ 52 ⋅ 7 ⋅ 11 ⋅ 13 = 448345497600

Schur multiplier: Order 6.

Outer automorphism group: Order 2.

Other names: Sz

Remarks: The 6 fold cover acts on a 12-dimensional lattice over the Eisenstein integers. It is not related to the Suzuki groups of Lie type.

O'Nan group, O'N

Order: 29 ⋅ 34 ⋅ 5 ⋅ 73 ⋅ 11 ⋅ 19 ⋅ 31 = 460815505920

Schur multiplier: Order 3.

Outer automorphism group: Order 2.

Other names: O'Nan–Sims group, O'NS, O–S

Remarks: The triple cover has two 45-dimensional representations over the field with 7 elements, exchanged by an outer automorphism.

Harada–Norton group, HN

Order: 214 ⋅ 36 ⋅ 56 ⋅ 7 ⋅ 11 ⋅ 19 = 273030912000000

Schur multiplier: Trivial.

Outer automorphism group: Order 2.

Other names:F5, D

Remarks: Centralizes an element of order 5 in the monster group.

Lyons group, Ly

Order: 28 ⋅ 37 ⋅ 56 ⋅ 7 ⋅ 11 ⋅ 31 ⋅ 37 ⋅ 67 = 51765179004000000

Schur multiplier: Trivial.

Outer automorphism group: Trivial.

Other names: Lyons–Sims group, LyS

Remarks: Has a 111-dimensional representation over the field with 5 elements.

Thompson group, Th

Order: 215 ⋅ 310 ⋅ 53 ⋅ 72 ⋅ 13 ⋅ 19 ⋅ 31 = 90745943887872000

Schur multiplier: Trivial.

Outer automorphism group: Trivial.

Other names:F3, E

Remarks: Centralizes an element of order 3 in the monster. Has a 248-dimensional representation which, when reduced modulo 3, leads to containment in E8(3).

Baby Monster group, B

Order:

   241 ⋅ 313 ⋅ 56 ⋅ 72 ⋅ 11 ⋅ 13 ⋅ 17 ⋅ 19 ⋅ 23 ⋅ 31 ⋅ 47
= 4154781481226426191177580544000000

Schur multiplier: Order 2.

Outer automorphism group: Trivial.

Other names:F2

Remarks: The double cover is contained in the monster group. It has a representation of dimension 4371 over the complex numbers (with no nontrivial invariant product), and a representation of dimension 4370 over the field with 2 elements preserving a commutative but non-associative product.

Fischer–Griess Monster group, M

Order:

   246 ⋅ 320 ⋅ 59 ⋅ 76 ⋅ 112 ⋅ 133 ⋅ 17 ⋅ 19 ⋅ 23 ⋅ 29 ⋅ 31 ⋅ 41 ⋅ 47 ⋅ 59 ⋅ 71
= 808017424794512875886459904961710757005754368000000000

Schur multiplier: Trivial.

Outer automorphism group: Trivial.

Other names:F1, M1, Monster group, Friendly giant, Fischer's monster.

Remarks: Contains all but 6 of the other sporadic groups as subquotients. Related to monstrous moonshine. The monster is the automorphism group of the 196,883-dimensional Griess algebra and the infinite-dimensional monster vertex operator algebra, and acts naturally on the monster Lie algebra.

Non-cyclic simple groups of small order

Order Factored order Group Schur multiplier Outer automorphism group
6022 ⋅ 3 ⋅ 5A5A1(4) ≃ A1(5)22
168 23 ⋅ 3 ⋅ 7A1(7) ≃ A2(2)22
36023 ⋅ 32 ⋅ 5A6A1(9) ≃ B2(2)′62×2
50423 ⋅ 32 ⋅ 7A1(8) ≃ 2G2(3)′13
66022 ⋅ 3 ⋅ 5 ⋅ 11A1(11)22
109222 ⋅ 3 ⋅ 7 ⋅ 13A1(13)22
244824 ⋅ 32 ⋅ 17A1(17)22
252023 ⋅ 32 ⋅ 5 ⋅ 7A762
342022 ⋅ 32 ⋅ 5 ⋅ 19A1(19)22
408024 ⋅ 3 ⋅ 5 ⋅ 17A1(16)14
561624 ⋅ 33 ⋅ 13A2(3)12
604825 ⋅ 33 ⋅ 72A2(9) ≃ G2(2)′12
607223 ⋅ 3 ⋅ 11 ⋅ 23A1(23)22
780023 ⋅ 3 ⋅ 52 ⋅ 13A1(25)22×2
792024 ⋅ 32 ⋅ 5 ⋅ 11 M11 11
982822 ⋅ 33 ⋅ 7 ⋅ 13A1(27)26
1218022 ⋅ 3 ⋅ 5 ⋅ 7 ⋅ 29A1(29)22
1488025 ⋅ 3 ⋅ 5 ⋅ 31A1(31)22
2016026 ⋅ 32 ⋅ 5 ⋅ 7A3(2) ≃ A822
2016026 ⋅ 32 ⋅ 5 ⋅ 7A2(4)3×42D12
2530822 ⋅ 32 ⋅ 19 ⋅ 37A1(37)22
2592026 ⋅ 34 ⋅ 52A3(4) ≃ B2(3)22
2912026 ⋅ 5 ⋅ 7 ⋅ 132B2(8)223
3273625 ⋅ 3 ⋅ 11 ⋅ 31A1(32)15
3444023 ⋅ 3 ⋅ 5 ⋅ 7 ⋅ 41A1(41)22
3973222 ⋅ 3 ⋅ 7 ⋅ 11 ⋅ 43A1(43)22
5188824 ⋅ 3 ⋅ 23 ⋅ 47A1(47)22
5880024 ⋅ 3 ⋅ 52 ⋅ 72A1(49)222
6240026 ⋅ 3 ⋅ 52 ⋅ 132A2(16)14
7441222 ⋅ 33 ⋅ 13 ⋅ 53A1(53)22
9504026 ⋅ 33 ⋅ 5 ⋅ 11 M12 22

(Complete for orders less than 100,000)

Hall (1972) lists the 56 non-cyclic simple groups of order less than a million.

See also

Notes

  1. There were several mistakes made in the initial calculations of the Schur multiplier, so some older books and papers list incorrect values. (This caused an error in the title of Janko's original 1976 paper [1] giving evidence for the existence of the group J4. At the time it was thought that the full covering group of M22 was 6⋅M22. In fact J4 has no subgroup 12⋅M22.)

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References

  1. Z. Janko (1976). "A new finite simple group of order 86,775,571,046,077,562,880 which possesses M24 and the full covering group of M22 as subgroups". J. Algebra. 42: 564–596. doi: 10.1016/0021-8693(76)90115-0 .

Further reading