GROUP OF ORDER 32 #42
GROUP #42
Extraspecial Dihedral(8)*Dihedral(8)
The MAGMA library number for G is 49
GrpPC : G of order 32 = 2^5
PC-Relations:
G.1^2 = G.5,
G.3^2 = G.5,
G.2^G.1 = G.2 * G.5,
G.3^G.1 = G.3 * G.5,
G.4^G.3 = G.4 * G.5
The center of G is abelian of type
[ 2 ]
.
The orders of the terms of the lower central series are
[ 32, 2, 1 ]
.
The orders of the terms of the upper central series are
[ 1, 2, 32 ]
.
The order of the Frattini subgroup is 2.
The exponent of G is 4.
G has 6 conjugacy classes
of maximal elementary abelian p-subgroups. The orders of the maximal
elementary abelian subgroups are
[ 8, 8, 8, 8, 8, 8 ]
.
The orders of the centralizers of the maximal elementary
abelian subgroups are
[ 8, 8, 8, 8, 8, 8 ]
.
The orders of the normalizers of the maximal elementary
abelian subgroups are
[ 32, 32, 32, 32, 32, 32 ]
.
The cohomology ring of G is the quotient of a polynomial
ring in the variables
[
z,
y,
x,
w,
v
]
in degrees
[ 1, 1, 1, 1, 4 ]
, by the ideal generated by the relations
z2
+ zy
+ zx
+ x2
+ xw
,
yx2
+ x3
+ yxw
+ xw2
.
The Hilbert series for the cohomology ring is
-t2 -t -1 / t5 -3t4+ 4t3
-4t2+ 3t -1.
Its numerator factors as
(
t2+t+1
)
.
Its denominator factors as
(
t-1
)3
(
t2+1
)
.
The Krull dimension of the cohomology ring is 3.
The cohomology ring is Cohen-Macaulay and the longest
regular sequence consists of the generators
y2
,
w2
,
v
.
Restrictions to Maximal Elementary Abelian
Subgroups
Subgroup E #1
Generated by
[ G.1 * G.2 * G.4, G.4 * G.5, G.5 ]
The cohomology ring of E is a polynomial ring in the
variables
z
,
y
,
x
.
The images of the generators of the cohomology of G
restricted to E are
x
,
x
,
0
,
z
+ x
,
z2y2
+ y4
+ z2yx
+ zy2x
+ z2x2
+ zyx2
+ y2x2
in the cohomology of E.
The kernel of the restriction to E (Minimal Prime) of the
cohomology of G is generated by
z
+ y
,
x
.
Subgroup E #2
Generated by
[ G.1 * G.2 * G.4, G.5, G.3 * G.4 * G.5 ]
The cohomology ring of E is a polynomial ring in the
variables
z
,
y
,
x
.
The images of the generators of the cohomology of G
restricted to E are
x
,
x
,
z
,
z
+ x
,
z4
+ z2y2
+ y4
+ z3x
+ z2yx
+ zy2x
+ zyx2
+ y2x2
in the cohomology of E.
The kernel of the restriction to E (Minimal Prime) of the
cohomology of G is generated by
z
+ x
+ w
,
y
+ x
+ w
.
Subgroup E #3
Generated by
[ G.2 * G.4 * G.5, G.5, G.1 * G.3 * G.4 * G.5 ]
The cohomology ring of E is a polynomial ring in the
variables
z
,
y
,
x
.
The images of the generators of the cohomology of G
restricted to E are
y
,
z
,
y
,
z
+ y
,
z2yx
+ zy2x
+ z2x2
+ zyx2
+ y2x2
+ x4
in the cohomology of E.
The kernel of the restriction to E (Minimal Prime) of the
cohomology of G is generated by
z
+ x
,
y
+ x
+ w
.
Subgroup E #4
Generated by
[ G.5, G.1 * G.3 * G.4 * G.5, G.2 * G.3 * G.4 * G.5 ]
The cohomology ring of E is a polynomial ring in the
variables
z
,
y
,
x
.
The images of the generators of the cohomology of G
restricted to E are
y
,
z
,
z
+ y
,
z
+ y
,
z4
+ z3y
+ z2y2
+ z2yx
+ zy2x
+ z2x2
+ zyx2
+ y2x2
+ x4
in the cohomology of E.
The kernel of the restriction to E (Minimal Prime) of the
cohomology of G is generated by
z
+ y
+ w
,
x
+ w
.
Subgroup E #5
Generated by
[ G.2 * G.4, G.4 * G.5, G.5 ]
The cohomology ring of E is a polynomial ring in the
variables
z
,
y
,
x
.
The images of the generators of the cohomology of G
restricted to E are
0
,
z
,
0
,
z
+ x
,
z2y2
+ y4
+ z2yx
+ zy2x
+ zyx2
+ y2x2
in the cohomology of E.
The kernel of the restriction to E (Minimal Prime) of the
cohomology of G is generated by
z
,
x
.
Subgroup E #6
Generated by
[ G.2 * G.3 * G.4, G.5, G.3 * G.4 * G.5 ]
The cohomology ring of E is a polynomial ring in the
variables
z
,
y
,
x
.
The images of the generators of the cohomology of G
restricted to E are
0
,
x
,
z
+ x
,
z
+ x
,
z4
+ z2y2
+ y4
+ z3x
+ z2yx
+ zy2x
+ zyx2
+ y2x2
+ zx3
+ x4
in the cohomology of E.
The kernel of the restriction to E (Minimal Prime) of the
cohomology of G is generated by
z
,
x
+ w
.
The nilradical of the cohomology of G is zero.
Restrictions to Maximal Subgroups
Maximal Subgroup H #1
Generated by
[ G.2 * G.4, G.2 * G.3, G.5, G.1 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number6
GrpPC of order 16 = 2^4
PC-Relations:
$.3^2 = $.4,
$.3^$.1 = $.3 * $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.1 * G.2 * G.4, G.3 * G.4, G.1 ]
of type
Cyclic(2) x Dihedral(8)
.
The images of the generators of the cohomology of G
restricted to H are
z
+ x
,
z
,
y
,
z
+ y
,
zy3
+ y4
+ zy2x
+ y2x2
+ zyw
+ w2
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
y
+ x
+ w
.
Maximal Subgroup H #2
Generated by
[ G.2 * G.3, G.4, G.5, G.1 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number8
GrpPC of order 16 = 2^4
PC-Relations:
$.1^2 = $.4,
$.3^2 = $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.1 * G.2 * G.3 * G.5, G.1 * G.4, G.1 ]
of type
AlmostExtraSpecial(16)
.
The images of the generators of the cohomology of G
restricted to H are
z
+ y
+ x
,
y
,
y
,
x
,
zy3
+ zy2x
+ yx3
+ w
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
y
+ x
.
Maximal Subgroup H #3
Generated by
[ G.4, G.2, G.5, G.3 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number6
GrpPC of order 16 = 2^4
PC-Relations:
$.3^2 = $.4,
$.3^$.1 = $.3 * $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.2 * G.3 * G.4, G.2 * G.3, G.3 * G.4 ]
of type
Cyclic(2) x Dihedral(8)
.
The images of the generators of the cohomology of G
restricted to H are
0
,
z
+ x
,
z
+ y
+ x
,
z
+ y
,
z4
+ z3y
+ zy3
+ y4
+ z3x
+ zy2x
+ y2x2
+ zyw
+ w2
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
z
.
Maximal Subgroup H #4
Generated by
[ G.1 * G.4, G.2, G.5, G.3 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number8
GrpPC of order 16 = 2^4
PC-Relations:
$.1^2 = $.4,
$.3^2 = $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.1 * G.3 * G.4, G.2 * G.3, G.3 ]
of type
AlmostExtraSpecial(16)
.
The images of the generators of the cohomology of G
restricted to H are
y
,
x
,
z
+ y
+ x
,
y
,
w
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
z
+ w
.
Maximal Subgroup H #5
Generated by
[ G.4, G.2, G.5, G.1 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number6
GrpPC of order 16 = 2^4
PC-Relations:
$.3^2 = $.4,
$.3^$.1 = $.3 * $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.1 * G.2 * G.4, G.1 * G.4, G.1 * G.2 ]
of type
Cyclic(2) x Dihedral(8)
.
The images of the generators of the cohomology of G
restricted to H are
z
+ y
+ x
,
z
+ y
,
0
,
z
+ x
,
z2y2
+ y4
+ y2x2
+ zyw
+ w2
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
x
.
Maximal Subgroup H #6
Generated by
[ G.4, G.5, G.3, G.1 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number8
GrpPC of order 16 = 2^4
PC-Relations:
$.1^2 = $.4,
$.3^2 = $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.1 * G.4 * G.5, G.4 * G.5, G.3 ]
of type
AlmostExtraSpecial(16)
.
The images of the generators of the cohomology of G
restricted to H are
z
,
0
,
x
,
z
+ y
,
yx3
+ w
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
y
.
Maximal Subgroup H #7
Generated by
[ G.1 * G.3 * G.5, G.4, G.2, G.5 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number6
GrpPC of order 16 = 2^4
PC-Relations:
$.3^2 = $.4,
$.3^$.1 = $.3 * $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.1 * G.3 * G.5, G.2, G.4 ]
of type
Cyclic(2) x Dihedral(8)
.
The images of the generators of the cohomology of G
restricted to H are
x
,
y
,
x
,
z
,
zyw
+ w2
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
z
+ x
.
Maximal Subgroup H #8
Generated by
[ G.1 * G.2 * G.5, G.4, G.5, G.3 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number6
GrpPC of order 16 = 2^4
PC-Relations:
$.3^2 = $.4,
$.3^$.1 = $.3 * $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.4 * G.5, G.1 * G.2, G.3 ]
of type
Cyclic(2) x Dihedral(8)
.
The images of the generators of the cohomology of G
restricted to H are
y
,
y
,
x
,
z
,
z2y2
+ y4
+ z3x
+ zy2x
+ y2x2
+ zyw
+ w2
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
z
+ y
.
Maximal Subgroup H #9
Generated by
[ G.1 * G.2 * G.5, G.1 * G.4, G.5, G.3 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number6
GrpPC of order 16 = 2^4
PC-Relations:
$.3^2 = $.4,
$.3^$.1 = $.3 * $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.2 * G.4, G.1 * G.2 * G.3, G.3 ]
of type
Cyclic(2) x Dihedral(8)
.
The images of the generators of the cohomology of G
restricted to H are
z
,
z
+ y
,
z
+ x
,
y
,
z3x
+ zy2x
+ y2x2
+ zyw
+ w2
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
z
+ y
+ w
.
Maximal Subgroup H #10
Generated by
[ G.1 * G.3 * G.5, G.1 * G.4, G.2, G.5 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number6
GrpPC of order 16 = 2^4
PC-Relations:
$.3^2 = $.4,
$.3^$.1 = $.3 * $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.1 * G.2 * G.4 * G.5, G.1 * G.2 * G.3, G.1 * G.3 * G.5 ]
of type
Cyclic(2) x Dihedral(8)
.
The images of the generators of the cohomology of G
restricted to H are
z
+ y
+ x
,
z
+ y
,
z
+ x
,
y
,
z3y
+ z2yx
+ zy2x
+ y2x2
+ zyw
+ w2
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
z
+ x
+ w
.
Maximal Subgroup H #11
Generated by
[ G.1 * G.2 * G.5, G.1 * G.3 * G.5, G.4, G.5 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number6
GrpPC of order 16 = 2^4
PC-Relations:
$.3^2 = $.4,
$.3^$.1 = $.3 * $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.2 * G.3 * G.4, G.2 * G.3, G.1 * G.3 * G.4 * G.5 ]
of type
Cyclic(2) x Dihedral(8)
.
The images of the generators of the cohomology of G
restricted to H are
y
,
z
+ x
,
z
+ y
+ x
,
z
+ y
,
z4
+ z3y
+ z2y2
+ z3x
+ zyw
+ w2
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
z
+ y
+ x
.
Maximal Subgroup H #12
Generated by
[ G.1 * G.2 * G.5, G.1 * G.3 * G.5, G.1 * G.4, G.5 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number8
GrpPC of order 16 = 2^4
PC-Relations:
$.1^2 = $.4,
$.3^2 = $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.2 * G.3, G.3 * G.4, G.1 * G.3 * G.5 ]
of type
AlmostExtraSpecial(16)
.
The images of the generators of the cohomology of G
restricted to H are
z
,
x
,
z
+ y
+ x
,
y
,
y4
+ z3x
+ yx3
+ w
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
z
+ y
+ x
+ w
.
Maximal Subgroup H #13
Generated by
[ G.2 * G.4, G.5, G.3, G.1 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number8
GrpPC of order 16 = 2^4
PC-Relations:
$.1^2 = $.4,
$.3^2 = $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.2 * G.4 * G.5, G.1 * G.2 * G.3 * G.4, G.3 ]
of type
AlmostExtraSpecial(16)
.
The images of the generators of the cohomology of G
restricted to H are
z
,
z
+ y
,
z
+ x
,
z
+ y
,
yx3
+ w
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
y
+ w
.
Maximal Subgroup H #14
Generated by
[ G.2, G.5, G.3, G.1 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number8
GrpPC of order 16 = 2^4
PC-Relations:
$.1^2 = $.4,
$.3^2 = $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.2 * G.3 * G.5, G.2 * G.5, G.1 ]
of type
AlmostExtraSpecial(16)
.
The images of the generators of the cohomology of G
restricted to H are
x
,
z
+ y
,
z
,
0
,
z3x
+ zy2x
+ x4
+ w
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
w
.
Maximal Subgroup H #15
Generated by
[ G.2, G.5, G.3 * G.4 * G.5, G.1 ]
.
The Group H is Isomorphic to the
Group of Order 16 Number6
GrpPC of order 16 = 2^4
PC-Relations:
$.3^2 = $.4,
$.3^$.1 = $.3 * $.4,
$.3^$.2 = $.3 * $.4
Generated by
[ G.3 * G.4, G.2 * G.5, G.1 ]
of type
Cyclic(2) x Dihedral(8)
.
The images of the generators of the cohomology of G
restricted to H are
x
,
z
,
y
,
y
,
z2y2
+ zy3
+ y4
+ z3x
+ zy2x
+ y2x2
+ zyw
+ w2
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
x
+ w
.
The essential cohomology of G is zero.
Inflations from Maximal Quotient Groups
Maximal Quotient Group Q #1
The kernel of the quotient is generated by
G.5
.
The group Q is abelian of type
[ 2, 2, 2, 2 ]
.
The cohomology ring of Q is a polynomial ring
with variables
z
,
y
,
x
,
w
in degrees
[ 1, 1, 1, 1 ]
The images of the generators of the cohomology of Q
inflated to G are
w
,
x
,
y
,
z
in the cohomology of G.
The kernel of the inflation to G of the
cohomology of Q is generated by
zy
+ y2
+ yw
+ xw
+ w2
,
zxw
+ x2w
+ zw2
+ w3
.
Action of Automorphisms
The groups of outer automorphisms of G has order 72, and is generated by 5
elements.
Automorphism #1
The order of the class of the automorphism in the
outer automorphism group is 3.
The images of the generators of G are
G.3
G.2 * G.4
G.1 * G.3 * G.5
G.2
G.5
.
The images of the generators of the cohomology of G
under the map induced by the automorphism are
x
,
y
+ w
,
z
+ x
,
y
,
z3x
+ y2x2
+ zy2w
+ z2xw
+ zyxw
+ x3w
+ yxw2
+ v
.
Automorphism #2
The order of the class of the automorphism in the
outer automorphism group is 3.
The images of the generators of G are
G.1 * G.5
G.1 * G.2 * G.4
G.3
G.1 * G.2 * G.3 * G.5
G.5
.
The images of the generators of the cohomology of G
under the map induced by the automorphism are
z
+ y
+ w
,
y
+ w
,
x
+ w
,
y
,
zy3
+ z2x2
+ y2x2
+ zyxw
+ y2xw
+ zyw2
+ zw3
+ yw3
+ v
.
Automorphism #3
The order of the class of the automorphism in the
outer automorphism group is 2.
The images of the generators of G are
G.3 * G.5
G.2 * G.3 * G.4
G.1
G.1 * G.3 * G.4 * G.5
G.5
.
The images of the generators of the cohomology of G
under the map induced by the automorphism are
x
+ w
,
y
,
z
+ y
+ w
,
y
+ w
,
y4
+ z3x
+ zy2w
+ y3w
+ z2xw
+ zyxw
+ y2w2
+ v
.
Automorphism #4
The order of the class of the automorphism in the
outer automorphism group is 2.
The images of the generators of G are
G.1
G.1 * G.2 * G.4 * G.5
G.3
G.4
G.5
.
The images of the generators of the cohomology of G
under the map induced by the automorphism are
z
+ y
,
y
,
x
,
y
+ w
,
zy3
+ y2w2
+ v
.
Automorphism #5
The order of the class of the automorphism in the
outer automorphism group is 2.
The images of the generators of G are
G.1 * G.2 * G.3 * G.4 * G.5
G.2
G.2 * G.3
G.2 * G.4
G.5
.
The images of the generators of the cohomology of G
under the map induced by the automorphism are
z
,
z
+ y
+ x
+ w
,
z
+ x
,
z
+ w
,
zy3
+ y2x2
+ z2xw
+ y2xw
+ x3w
+ zyw2
+ xw3
+ v
.
CHECKS
paramflag =
true
qregflagflag =
true
cmflag =
true
essflag =
true
centflag =
true
THE COMPUTATION IS COMPLETE