GROUP OF ORDER 32 #18
GROUP #18
The MAGMA library number for G is 2
GrpPC : G of order 32 = 2^5
PC-Relations:
G.1^2 = G.3,
G.2^2 = G.4,
G.2^G.1 = G.2 * G.5
The center of G is abelian of type
[ 2, 2, 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, 8, 32 ]
.
The order of the Frattini subgroup is 8.
The exponent of G is 4.
G has a unique maximal elementary abelian subgroup which is
central in G and has order 8.
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, 2, 2, 2, 2, 2 ]
, by the ideal generated by the relations
z2
,
zy
,
y2
,
zx
,
yx
+ zv
,
yv
,
x2
,
xv
,
v2
.
The Hilbert series for the cohomology ring is
-t2 -t -1 / t5 -t4 -2t3+
2t2+ t -1.
Its numerator factors as
(
t2+t+1
)
.
Its denominator factors as
(
t-1
)3
(
t+1
)2
.
The Krull dimension of the cohomology ring is 3.
The cohomology ring is Cohen-Macaulay and the longest
regular sequence consists of the generators
w
,
u
,
t
.
Restriction to the Maximal Elementary Abelian
Subgroup
Generated by
[ G.3, G.3 * G.4, 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
,
0
,
0
,
z2
+ y2
,
0
,
x2
,
y2
+ x2
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
.
This ideal is also the nilradical of the
cohomology of G.
It is nilpotent of degree 3.
Restrictions to Maximal Subgroups
Maximal Subgroup H #1
Generated by
[ G.3, G.2, G.5, G.4 ]
.
The group H is abelian of type
[ 4, 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
0
,
z
,
zy
,
y2
,
zx
,
zx
+ x2
,
y2
+ w
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
z
.
Maximal Subgroup H #2
Generated by
[ G.3, G.5, G.4, G.1 ]
.
The group H is abelian of type
[ 4, 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
,
0
,
zx
,
w
,
zy
,
zx
+ x2
,
y2
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
y
.
Maximal Subgroup H #3
Generated by
[ G.3, G.1 * G.2 * G.5, G.5, G.4 ]
.
The group H is abelian of type
[ 4, 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
,
z
,
zx
,
w
,
zy
+ zx
,
x2
+ w
,
y2
+ w
in the cohomology of H.
The kernel of the restriction to H of the
cohomology of G is generated by
z
+ y
.
The essential cohomology of G is
generated as an ideal by
zv
.
It is nilpotent of degree 2.
The annihilator of the Essential Cohomology has dimension
3
.
The essential cohomology is a free module over
the polynomial subring Q of the cohomology ring of G generated by
w
,
u
,
t
.
The essential cohomology is generated as a module
over Q by the elements
[]
[]
[ zv ]
Inflations from Maximal Quotient Groups
Maximal Quotient Group Q #1
The kernel of the quotient is generated by
G.4
.
The Group Q is Isomorphic to the
Group of Order 16 Number9
GrpPC of order 16 = 2^4
PC-Relations:
$.1^2 = $.3 * $.4,
$.2^2 = $.3,
$.2^$.1 = $.2 * $.4
.
The generators of G have images
[ pcy.1 * pcy.2 * pcy.3, pcy.2 ]
in the quotient group.
The images of the generators of the cohomology of Q
inflated to G are
y
,
z
+ y
,
x
,
u
,
w
in the cohomology of G.
The kernel of the inflation to G of the
cohomology of Q is generated by
y2
.
Maximal Quotient Group Q #2
The kernel of the quotient is generated by
G.3 * G.4 * G.5
.
The Group Q is Isomorphic to the
Group of Order 16 Number9
GrpPC of order 16 = 2^4
PC-Relations:
$.1^2 = $.3 * $.4,
$.2^2 = $.3,
$.2^$.1 = $.2 * $.4
.
The generators of G have images
[ pcy.2, pcy.1 ]
in the quotient group.
The images of the generators of the cohomology of Q
inflated to G are
z
,
y
,
x
+ v
,
x
+ w
+ u
,
w
+ t
in the cohomology of G.
The kernel of the inflation to G of the
cohomology of Q is generated by
y2
.
Maximal Quotient Group Q #3
The kernel of the quotient is generated by
G.3 * G.5
.
The Group Q is Isomorphic to the
Group of Order 16 Number10
GrpPC of order 16 = 2^4
PC-Relations:
$.1^2 = $.3,
$.2^2 = $.3,
$.2^$.1 = $.2 * $.4
.
The generators of G have images
[ pcy.2, pcy.1 * pcy.2 * pcy.3 ]
in the quotient group.
The images of the generators of the cohomology of Q
inflated to G are
z
,
z
+ y
,
x
+ w
+ u
,
t
in the cohomology of G.
The kernel of the inflation to G of the
cohomology of Q is generated by
y2
.
Maximal Quotient Group Q #4
The kernel of the quotient is generated by
G.5
.
The group Q is abelian of type
[ 4, 4 ]
.
The cohomology ring of Q is a the quotient of
a polynomial ring in the variables
[
z,
y,
x,
w
]
, in degrees
[ 1, 1, 2, 2 ]
, by the ideal of relations
z2
,
y2
.
The images of the generators of the cohomology of Q
inflated to G are
y
,
z
,
t
,
w
in the cohomology of G.
The kernel of the inflation to G of the
cohomology of Q is generated by
zy
.
Maximal Quotient Group Q #5
The kernel of the quotient is generated by
G.4 * G.5
.
The Group Q is Isomorphic to the
Group of Order 16 Number10
GrpPC of order 16 = 2^4
PC-Relations:
$.1^2 = $.3,
$.2^2 = $.3,
$.2^$.1 = $.2 * $.4
.
The generators of G have images
[ pcy.1 * pcy.2 * pcy.3, pcy.2 ]
in the quotient group.
The images of the generators of the cohomology of Q
inflated to G are
y
,
z
+ y
,
v
+ u
+ t
,
w
in the cohomology of G.
The kernel of the inflation to G of the
cohomology of Q is generated by
y2
.
Maximal Quotient Group Q #6
The kernel of the quotient is generated by
G.3 * G.4
.
The Group Q is Isomorphic to the
Group of Order 16 Number10
GrpPC of order 16 = 2^4
PC-Relations:
$.1^2 = $.3,
$.2^2 = $.3,
$.2^$.1 = $.2 * $.4
.
The generators of G have images
[ pcy.2, pcy.1 ]
in the quotient group.
The images of the generators of the cohomology of Q
inflated to G are
z
,
y
,
u
,
w
+ t
in the cohomology of G.
The kernel of the inflation to G of the
cohomology of Q is generated by
y2
.
Maximal Quotient Group Q #7
The kernel of the quotient is generated by
G.3
.
The Group Q is Isomorphic to the
Group of Order 16 Number9
GrpPC of order 16 = 2^4
PC-Relations:
$.1^2 = $.3 * $.4,
$.2^2 = $.3,
$.2^$.1 = $.2 * $.4
.
The generators of G have images
[ pcy.2, pcy.1 * pcy.2 * pcy.3 ]
in the quotient group.
The images of the generators of the cohomology of Q
inflated to G are
z
,
z
+ y
,
v
,
u
,
t
in the cohomology of G.
The kernel of the inflation to G of the
cohomology of Q is generated by
y2
.
Action of Automorphisms
The groups of outer automorphisms of G has order 96, and is generated by 6
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.3
G.2
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
,
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.4
G.2
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
,
x
,
w
,
v
,
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.2 * G.3
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
,
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.2 * G.4
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
,
x
,
w
,
v
,
u
,
t
.
Automorphism #5
The order of the class of the automorphism in the
outer automorphism group is 4.
The images of the generators of G are
G.1 * G.2
G.2
G.3 * G.4 * G.5
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
,
x
+ v
,
x
+ w
+ u
,
w
+ t
.
Automorphism #6
The order of the class of the automorphism in the
outer automorphism group is 2.
The images of the generators of G are
The images of the generators of the cohomology of G
under the map induced by the automorphism are
y
,
z
,
v
,
t
,
x
,
u
,
w
.
CHECKS
paramflag =
true
qregflagflag =
true
cmflag =
true
essflag =
true
centflag =
true
THE COMPUTATION IS COMPLETE