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G = C8:9M4(2)  order 128 = 27

3rd semidirect product of C8 and M4(2) acting via M4(2)/C2xC4=C2

p-group, metabelian, nilpotent (class 2), monomial

Aliases: C8:9M4(2), C23.26C42, C42.743C23, C4:C8.18C4, (C4xC8).35C4, C8:C8:19C2, C8:C4.11C4, C4.9(C8:C4), C4.53(C8oD4), C22:C8.17C4, (C2xC4).60C42, (C22xC8).44C4, C2.5(C4xM4(2)), C42.242(C2xC4), (C4xC8).360C22, C4.57(C2xM4(2)), (C2xC4).41M4(2), C22.8(C8:C4), (C4xM4(2)).13C2, (C2xM4(2)).21C4, C22.40(C2xC42), C2.6(C8o2M4(2)), C42.12C4.41C2, (C2xC42).1030C22, (C2xC4xC8).59C2, C2.5(C2xC8:C4), (C2xC8).117(C2xC4), (C2xC4).580(C22xC4), (C22xC4).392(C2xC4), SmallGroup(128,183)

Series: Derived Chief Lower central Upper central Jennings

C1C22 — C8:9M4(2)
C1C2C22C2xC4C42C2xC42C2xC4xC8 — C8:9M4(2)
C1C22 — C8:9M4(2)
C1C42 — C8:9M4(2)
C1C22C22C42 — C8:9M4(2)

Generators and relations for C8:9M4(2)
 G = < a,b,c | a8=b8=c2=1, bab-1=a5, ac=ca, cbc=b5 >

Subgroups: 132 in 104 conjugacy classes, 76 normal (26 characteristic)
C1, C2, C2, C4, C4, C22, C22, C22, C8, C8, C2xC4, C2xC4, C2xC4, C23, C42, C2xC8, C2xC8, M4(2), C22xC4, C4xC8, C4xC8, C8:C4, C22:C8, C4:C8, C2xC42, C22xC8, C2xM4(2), C8:C8, C2xC4xC8, C4xM4(2), C42.12C4, C8:9M4(2)
Quotients: C1, C2, C4, C22, C2xC4, C23, C42, M4(2), C22xC4, C8:C4, C2xC42, C2xM4(2), C8oD4, C2xC8:C4, C4xM4(2), C8o2M4(2), C8:9M4(2)

Smallest permutation representation of C8:9M4(2)
On 64 points
Generators in S64
(1 2 3 4 5 6 7 8)(9 10 11 12 13 14 15 16)(17 18 19 20 21 22 23 24)(25 26 27 28 29 30 31 32)(33 34 35 36 37 38 39 40)(41 42 43 44 45 46 47 48)(49 50 51 52 53 54 55 56)(57 58 59 60 61 62 63 64)
(1 19 36 54 27 43 12 59)(2 24 37 51 28 48 13 64)(3 21 38 56 29 45 14 61)(4 18 39 53 30 42 15 58)(5 23 40 50 31 47 16 63)(6 20 33 55 32 44 9 60)(7 17 34 52 25 41 10 57)(8 22 35 49 26 46 11 62)
(17 41)(18 42)(19 43)(20 44)(21 45)(22 46)(23 47)(24 48)(49 62)(50 63)(51 64)(52 57)(53 58)(54 59)(55 60)(56 61)

G:=sub<Sym(64)| (1,2,3,4,5,6,7,8)(9,10,11,12,13,14,15,16)(17,18,19,20,21,22,23,24)(25,26,27,28,29,30,31,32)(33,34,35,36,37,38,39,40)(41,42,43,44,45,46,47,48)(49,50,51,52,53,54,55,56)(57,58,59,60,61,62,63,64), (1,19,36,54,27,43,12,59)(2,24,37,51,28,48,13,64)(3,21,38,56,29,45,14,61)(4,18,39,53,30,42,15,58)(5,23,40,50,31,47,16,63)(6,20,33,55,32,44,9,60)(7,17,34,52,25,41,10,57)(8,22,35,49,26,46,11,62), (17,41)(18,42)(19,43)(20,44)(21,45)(22,46)(23,47)(24,48)(49,62)(50,63)(51,64)(52,57)(53,58)(54,59)(55,60)(56,61)>;

G:=Group( (1,2,3,4,5,6,7,8)(9,10,11,12,13,14,15,16)(17,18,19,20,21,22,23,24)(25,26,27,28,29,30,31,32)(33,34,35,36,37,38,39,40)(41,42,43,44,45,46,47,48)(49,50,51,52,53,54,55,56)(57,58,59,60,61,62,63,64), (1,19,36,54,27,43,12,59)(2,24,37,51,28,48,13,64)(3,21,38,56,29,45,14,61)(4,18,39,53,30,42,15,58)(5,23,40,50,31,47,16,63)(6,20,33,55,32,44,9,60)(7,17,34,52,25,41,10,57)(8,22,35,49,26,46,11,62), (17,41)(18,42)(19,43)(20,44)(21,45)(22,46)(23,47)(24,48)(49,62)(50,63)(51,64)(52,57)(53,58)(54,59)(55,60)(56,61) );

G=PermutationGroup([[(1,2,3,4,5,6,7,8),(9,10,11,12,13,14,15,16),(17,18,19,20,21,22,23,24),(25,26,27,28,29,30,31,32),(33,34,35,36,37,38,39,40),(41,42,43,44,45,46,47,48),(49,50,51,52,53,54,55,56),(57,58,59,60,61,62,63,64)], [(1,19,36,54,27,43,12,59),(2,24,37,51,28,48,13,64),(3,21,38,56,29,45,14,61),(4,18,39,53,30,42,15,58),(5,23,40,50,31,47,16,63),(6,20,33,55,32,44,9,60),(7,17,34,52,25,41,10,57),(8,22,35,49,26,46,11,62)], [(17,41),(18,42),(19,43),(20,44),(21,45),(22,46),(23,47),(24,48),(49,62),(50,63),(51,64),(52,57),(53,58),(54,59),(55,60),(56,61)]])

56 conjugacy classes

class 1 2A2B2C2D2E4A···4L4M···4R8A···8P8Q···8AF
order1222224···44···48···88···8
size1111221···12···22···24···4

56 irreducible representations

dim11111111111222
type+++++
imageC1C2C2C2C2C4C4C4C4C4C4M4(2)M4(2)C8oD4
kernelC8:9M4(2)C8:C8C2xC4xC8C4xM4(2)C42.12C4C4xC8C8:C4C22:C8C4:C8C22xC8C2xM4(2)C8C2xC4C4
# reps14111444444888

Matrix representation of C8:9M4(2) in GL4(F17) generated by

4000
0400
0001
0040
,
51500
61200
0072
00910
,
1000
51600
0010
0001
G:=sub<GL(4,GF(17))| [4,0,0,0,0,4,0,0,0,0,0,4,0,0,1,0],[5,6,0,0,15,12,0,0,0,0,7,9,0,0,2,10],[1,5,0,0,0,16,0,0,0,0,1,0,0,0,0,1] >;

C8:9M4(2) in GAP, Magma, Sage, TeX

C_8\rtimes_9M_4(2)
% in TeX

G:=Group("C8:9M4(2)");
// GroupNames label

G:=SmallGroup(128,183);
// by ID

G=gap.SmallGroup(128,183);
# by ID

G:=PCGroup([7,-2,2,2,-2,2,-2,2,56,925,120,758,136,172]);
// Polycyclic

G:=Group<a,b,c|a^8=b^8=c^2=1,b*a*b^-1=a^5,a*c=c*a,c*b*c=b^5>;
// generators/relations

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