GROUP OF ORDER 64 #99
GROUP #99
The MAGMA library number for G is 116
GrpPC : G of order 64 = 2^6
PC-Relations:
G.1^2 = G.3,
G.2^2 = G.3,
G.3^2 = G.6,
G.4^G.1 = G.4 * G.5,
G.4^G.2 = G.4 * G.6
The center of G is abelian of type
[ 2, 4 ]
.
The orders of the terms of the lower central series are
[ 64, 4, 1 ]
.
The orders of the terms of the upper central series are
[ 1, 8, 64 ]
.
The order of the Frattini subgroup is 8.
The exponent of G is 8.
G has 2 conjugacy classes
of maximal elementary abelian p-subgroups. The orders of the maximal
elementary abelian subgroups are
[ 8, 8 ]
.
The orders of the centralizers of the maximal elementary
abelian subgroups are
[ 32, 16 ]
.
The orders of the normalizers of the maximal elementary
abelian subgroups are
[ 64, 64 ]
.
The cohomology ring of G is the quotient of a polynomial
ring in the variables
[
z,
y,
x,
w,
v,
u,
t
]
in degrees
[ 1, 1, 1, 2, 3, 3, 4 ]
, by the ideal generated by the relations
z2
+ y2
,
zx
,
yx2
,
zv
+ yu
,
yv
+ zu
,
xv
,
zy3w
+ zy2u
+ zyt
+ vu
,
y4w
+ y3u
+ y2t
+ u2
,
v2
+ u2
.
The Hilbert series for the cohomology ring is
-t3 -t -1 / t6 -2t5+ t4
-t2+ 2t -1.
Its numerator factors as
(
t3+t+1
)
.
Its denominator factors as
(
t-1
)3
(
t+1
)
(
t2+1
)
.
The Krull dimension of the cohomology ring is 3.
The longest regular sequence consists of the generators
w
,
t
.
A homogeneous set of parameters is the set
w
,
t
,
zy
+ yx
+ x2
of degrees
[ 2, 4, 2 ]
.
The hypercohomolgy spectral sequence has E2
term:
ROW
(1)
: []
[]
[ yx ]
ROW
(0)
: [1]
[ z, y, x ]
[ x2, y2, yx ]
[ u, v ]
[ xu, zu, yu ]
[ x2u ]
Restrictions to Maximal Elementary Abelian
Subgroups
Subgroup E #1
Generated by
[ G.6, G.5, G.1 * G.2 * G.3 * 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
z
,
z
,
0
,
zy
+ y2
,
z2y
+ zx2
,
z2y
+ zx2
,
z2x2
+ 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
,
x
,
v
+ u
.
Subgroup E #2
Generated by
[ G.6, G.4 * G.5 * G.6, 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
,
0
,
z
,
zy
+ y2
,
0
,
0
,
z2x2
+ 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
,
v
,
u
.
The nilradical of the cohomology of G is
generated by
z
+ y
,
v
+ u
.
It is nilpotent of degree 2.
Restrictions to Maximal Subgroups
Maximal Subgroup H #1
Generated by
[ G.2, G.1, G.6, G.3, G.5 ]
.
The group H is abelian of type
[ 8, 2, 2 ]
The cohomology ring of H is a the quotient of
a polynomial ring in the variables
[
z,
y,
x,
w
]
, in degrees
[ 1, 1, 1, 2 ]
, by the ideal of relations
z2
.
The images of the generators of the cohomology of G
restricted to H are
z
+ y
,
y
,
0
,
zx
+ yx
+ x2
,
y2x
+ zw
+ yw
,
zyx
+ y2x
+ yw
,
y2w
+ 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 #2
Generated by
[ G.1 * G.2, G.4, G.6, G.3, G.5 ]
.
The Group H is Isomorphic to the
Group of Order 32 Number14
GrpPC of order 32 = 2^5
PC-Relations:
$.1^2 = $.4 * $.5,
$.2^2 = $.4,
$.2^$.1 = $.2 * $.5,
$.3^$.2 = $.3 * $.5
Generated by
[ G.1 * G.2 * G.4, G.4 * G.5 * G.6, G.3 * G.4 * G.5 ]
of type
Cyclic(4) x Dihedral(8)
.
The images of the generators of the cohomology of G
restricted to H are
y
,
y
,
z
+ y
+ x
,
w
+ v
,
y3
+ yv
,
y3
+ zx2
+ yv
,
y2w
+ x2w
+ v2
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 #3
Generated by
[ G.1 * G.4 * G.5, G.2, G.6, G.3, G.5 ]
.
The Group H is Isomorphic to the
Group of Order 32 Number19
GrpPC of order 32 = 2^5
PC-Relations:
$.1^2 = $.3,
$.2^2 = $.4,
$.4^2 = $.5,
$.2^$.1 = $.2 * $.5
Generated by
[ G.1 * G.4 * G.5, G.1 * G.2 * G.3 * G.4 ]
.
The images of the generators of the cohomology of G
restricted to H are
z
+ y
,
z
,
z
+ y
,
zy
+ x
,
zx
+ yx
+ zw
+ yw
,
zx
+ zw
,
zyx
+ zyw
+ x2
+ 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 #4
Generated by
[ G.4, G.1, G.6, G.3, G.5 ]
.
The Group H is Isomorphic to the
Group of Order 32 Number20
GrpPC of order 32 = 2^5
PC-Relations:
$.1^2 = $.2,
$.2^2 = $.4,
$.3^$.1 = $.3 * $.5
Generated by
[ G.4, G.1 ]
.
The images of the generators of the cohomology of G
restricted to H are
z
,
0
,
y
,
v
,
zw
,
yx
,
y2w
+ w2
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
y
.
Maximal Subgroup H #5
Generated by
[ G.2 * G.4 * G.6, G.1, G.6, G.3, G.5 ]
.
The Group H is Isomorphic to the
Group of Order 32 Number21
GrpPC of order 32 = 2^5
PC-Relations:
$.1^2 = $.3,
$.2^2 = $.4 * $.5,
$.3^2 = $.4,
$.2^$.1 = $.2 * $.5
Generated by
[ G.1 * G.2 * G.3 * G.4 * G.6, G.2 * G.4 * G.6 ]
.
The images of the generators of the cohomology of G
restricted to H are
y
,
z
+ y
,
z
+ y
,
y2
+ x
+ w
,
yw
,
zw
+ yw
,
y2w
+ w2
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 #6
Generated by
[ G.1 * G.2, G.2 * G.4 * G.6, G.6, G.3, G.5 ]
.
The Group H is Isomorphic to the
Group of Order 32 Number20
GrpPC of order 32 = 2^5
PC-Relations:
$.1^2 = $.2,
$.2^2 = $.4,
$.3^$.1 = $.3 * $.5
Generated by
[ G.2 * G.4 * G.6, G.1 * G.2 * G.3 ]
.
The images of the generators of the cohomology of G
restricted to H are
y
,
z
+ y
,
z
,
v
,
y3
+ yw
+ yv
,
y3
+ zw
+ yw
+ zv
+ yv
,
y2w
+ w2
+ v2
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 #7
Generated by
[ G.4, G.2, G.6, G.3, G.5 ]
.
The Group H is Isomorphic to the
Group of Order 32 Number13
GrpPC of order 32 = 2^5
PC-Relations:
$.1^2 = $.4,
$.2^2 = $.4,
$.4^2 = $.5,
$.2^$.1 = $.2 * $.5,
$.3^$.1 = $.3 * $.5,
$.3^$.2 = $.3 * $.5
Generated by
[ G.2 * G.3 * G.4 * G.5, G.2, G.4 * G.6 ]
of type
Cyclic(2) x Group(16)#11
.
The images of the generators of the cohomology of G
restricted to H are
0
,
z
+ y
,
z
+ x
,
zx
,
z2y
+ zy2
+ z2x
+ zyx
,
w
,
zy3
+ zyx2
+ v
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
z
.
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.6
.
The Group Q is Isomorphic to the
Group of Order 32 Number14
GrpPC of order 32 = 2^5
PC-Relations:
$.1^2 = $.4 * $.5,
$.2^2 = $.4,
$.2^$.1 = $.2 * $.5,
$.3^$.2 = $.3 * $.5
of type
Cyclic(4) x Dihedral(8)
.
The generators of G have images
[ pcy.1 * pcy.2 * pcy.4 * pcy.5, pcy.1 * pcy.3 * pcy.4 * pcy.5, pcy.1 * pcy.4 ]
in the quotient group.
The images of the generators of the cohomology of Q
inflated to G are
z
+ y
+ x
,
x
,
y
,
yx
,
yx
+ w
in the cohomology of G.
The kernel of the inflation to G of the
cohomology of Q is generated by
yx
+ w
,
yw
.
Maximal Quotient Group Q #2.
The kernel of the quotient is generated by
G.5 * G.6
.
The Group Q is Isomorphic to the
Group of Order 32 Number13
GrpPC of order 32 = 2^5
PC-Relations:
$.1^2 = $.4,
$.2^2 = $.4,
$.4^2 = $.5,
$.2^$.1 = $.2 * $.5,
$.3^$.1 = $.3 * $.5,
$.3^$.2 = $.3 * $.5
of type
Cyclic(2) x Group(16)#11
.
The generators of G have images
[ pcy.1 * pcy.2, pcy.2, pcy.1 * pcy.3 * pcy.4 ]
in the quotient group.
The images of the generators of the cohomology of Q
inflated to G are
z
+ x
,
y
+ x
,
z
,
zw
+ yw
+ v
+ u
,
x4
+ z2w
+ yxw
+ w2
+ zv
+ t
in the cohomology of G.
The kernel of the inflation to G of the
cohomology of Q is generated by
zx
+ x2
.
Maximal Quotient Group Q #3.
The kernel of the quotient is generated by
G.5
.
The Group Q is Isomorphic to the
Group of Order 32 Number17
GrpPC of order 32 = 2^5
PC-Relations:
$.1^2 = $.4,
$.2^2 = $.4,
$.3^2 = $.5,
$.4^2 = $.5,
$.2^$.1 = $.2 * $.5,
$.3^$.1 = $.3 * $.5
.
The generators of G have images
[ pcy.3 * pcy.4, pcy.1 * pcy.3 * pcy.4, pcy.2 * pcy.3 * pcy.5 ]
in the quotient group.
The images of the generators of the cohomology of Q
inflated to G are
y
,
z
,
z
+ y
+ x
,
z2y2
+ t
in the cohomology of G.
The kernel of the inflation to G of the
cohomology of Q is generated by
zy
+ y2
+ yx
.
The depth-essential cohomology of G
The depth-essential cohomology of G is the intersection
of the restrictions to the centralizers of the maximal elementary abelian
p-subgroups of rank d+1 where d is the depth of the
cohomology ring. For this group the depth is 2.
There are 2 conjugacy classes of subgroups which
are centralizers of elementary abelian subgroups of rank 3. They are represented
by the subgroups generated by
[ G.1 * G.2, G.1 * G.6, G.1 * G.5 ]
[ G.4, G.3 * G.4 * G.6, G.3 * G.4 * G.5 ]
.
The depth-essential cohomology of G is
generated as an ideal by
yx
.
The annihilator of the depth-essential cohomology has dimension
2
.
The depth-essential cohomology is a free module over
the polynomial subring Q of the cohomology ring of G generated by
w
,
t
.
The depth-essential cohomology is generated as a module
over Q by the elements
[]
[ yx ]
Action of Automorphisms
The groups of outer automorphisms of G has order 32, and is generated by 5
elements.
Automorphism #1
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.5
G.2 * G.6
G.3
G.4 * G.6
G.5
G.6
.
The images of the generators of the cohomology of G
under the map induced by the automorphism are
z
,
y
,
x
,
w
,
v
,
u
,
t
.
Automorphism #2
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.6
G.2
G.3
G.4
G.5
G.6
.
The images of the generators of the cohomology of G
under the map induced by the automorphism are
z
,
y
,
x
,
w
,
zy2
+ v
,
y3
+ u
,
t
.
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.1 * G.6
G.2 * G.6
G.3
G.4 * G.6
G.5
G.6
.
The images of the generators of the cohomology of G
under the map induced by the automorphism are
z
,
y
,
x
,
w
,
v
,
u
,
t
.
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.5 * G.6
G.2 * G.5 * G.6
G.3
G.4 * G.5 * G.6
G.5
G.6
.
The images of the generators of the cohomology of G
under the map induced by the automorphism are
z
,
y
,
x
,
zy
+ y2
+ yx
+ w
,
zy2
+ y3
+ v
,
zy2
+ y3
+ u
,
t
.
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.3
G.2 * G.3
G.3 * G.6
G.4 * G.6
G.5
G.6
.
The images of the generators of the cohomology of G
under the map induced by the automorphism are
z
,
y
,
x
,
w
,
v
,
u
,
t
.
CHECKS
paramflag =
true
qregflagflag =
true
cmflag =
false
essflag =
true
centflag =
true
THE COMPUTATION IS COMPLETE