Finite Group Databasebeta
Cayley diagram

D19 #164

order38
isoclinismisoclinic class of D19
automorphismAut(G) = AGL(1,𝔽19) (order 342) · Inn(G) = G · Out(G) = C9
holomorphG ⋊ Aut(G) = #20266599⋊C2
homologyAbelianization (H1) = C2 · Schur multiplier (H2) = C1

Aliases

dihedralD19
unambiguous semidirect productC19⋊C2

Splittings

Fitting, socle, derived, SylowC19 ⋊ C2

Subgroups

subgroupG/H
center, Frattini, hypercenterC1G
commutator, Fitting, socle, cosocle, hypocenterC19C2
LCSG ▷ C19
UCSC1

4 conjugacy classes of subgroups.

Full subgroup data →

Presentation

minimal degreeμ(G) = 19
transitive degreeμt(G) = 19

A minimal faithful permutation representation — 2 generators on 19 points:

(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19);(2,19)(3,18)(4,17)(5,16)(6,15)(7,14)(8,13)(9,12)(10,11)

Polycyclic presentation:

2,19|b^a=b^18

Conjugacy classes & character table

C1C2C3C4C5C6C7C8C9C10C11
size122222222219
order11919191919191919192
χ111111111111
χ21111111111-1
χ32ζ+ζ18ζ2+ζ17ζ3+ζ16ζ4+ζ15ζ5+ζ14ζ6+ζ13ζ7+ζ12ζ8+ζ11ζ9+ζ100
χ42ζ2+ζ17ζ4+ζ15ζ6+ζ13ζ8+ζ11ζ9+ζ10ζ7+ζ12ζ5+ζ14ζ3+ζ16ζ+ζ180
χ52ζ3+ζ16ζ6+ζ13ζ9+ζ10ζ7+ζ12ζ4+ζ15ζ+ζ18ζ2+ζ17ζ5+ζ14ζ8+ζ110
χ62ζ4+ζ15ζ8+ζ11ζ7+ζ12ζ3+ζ16ζ+ζ18ζ5+ζ14ζ9+ζ10ζ6+ζ13ζ2+ζ170
χ72ζ5+ζ14ζ9+ζ10ζ4+ζ15ζ+ζ18ζ6+ζ13ζ8+ζ11ζ3+ζ16ζ2+ζ17ζ7+ζ120
χ82ζ6+ζ13ζ7+ζ12ζ+ζ18ζ5+ζ14ζ8+ζ11ζ2+ζ17ζ4+ζ15ζ9+ζ10ζ3+ζ160
χ92ζ7+ζ12ζ5+ζ14ζ2+ζ17ζ9+ζ10ζ3+ζ16ζ4+ζ15ζ8+ζ11ζ+ζ18ζ6+ζ130
χ102ζ8+ζ11ζ3+ζ16ζ5+ζ14ζ6+ζ13ζ2+ζ17ζ9+ζ10ζ+ζ18ζ7+ζ12ζ4+ζ150
χ112ζ9+ζ10ζ+ζ18ζ8+ζ11ζ2+ζ17ζ7+ζ12ζ3+ζ16ζ6+ζ13ζ4+ζ15ζ5+ζ140

Here ζ is a primitive root of unity of order 19 (ζ19 = 1).

Relationships

maximal subgroup ofC2×D19, D19⋊C3, C3×D19, …
maximal normal subgroup ofC2×D19, D19⋊C3, C3×D19, …
maximal quotient ofDic19, C2×D19, C3×D19, …

GAP

Construct this group in GAP via the SmallGroups library:

gap> SmallGroup(38, 1);