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
[
z^2,
z*y,
y^2,
z*x,
y*x + z*v,
y*v,
x^2,
x*v,
v^2
]
The Hilbert series for the cohomology ring is (-t^2 - t - 1)/(t^5 - t^4 - 2*t^3
+ 2*t^2 + t - 1)
Its numerator factors as
( t^2 + 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.4, G.3 * G.5, G.3 * G.4 ]
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,
y^2 + x^2,
0,
y^2,
z^2 + x^2
]
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.
Restrictions to Maximal Subgroups
Maximal Subgroup H # 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
[
z^2
]
The images of the generators of the cohomology of G
restricted to H are
[
0,
z,
z*y,
y^2,
z*x,
z*x + x^2,
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
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
[
z^2
]
The images of the generators of the cohomology of G
restricted to H are
[
z,
z,
z*y + z*x,
y^2 + w,
z*x,
x^2 + w,
w
]
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
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
[
z^2
]
The images of the generators of the cohomology of G
restricted to H are
[
z,
0,
z*x,
w,
z*y,
z*x + x^2,
y^2
]
in the cohomology of H
The kernel of the restriction to H of the cohomology of G
is generated by
[
y
]
The essential cohomology of G is
generated as an ideal by the elements
[
z*v
]
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
[]
[]
[
z*v
]
CHECKS
paramflag = true
qregflagflag = true
cmflag = true
essflag = true
centflag = true
THE COMPUTATION IS COMPLETE