GROUP OF ORDER 32 #40

GROUP #40

The MAGMA library number for G is 32

GrpPC : G of order 32 = 2^5 PC-Relations: G.1^2 = G.4 * G.5, G.2^2 = G.4 * G.5, G.3^2 = G.5, G.2^G.1 = G.2 * G.4, G.3^G.2 = G.3 * G.5

The center of G is abelian of type [ 2, 2 ] .
The orders of the terms of the lower central series are [ 32, 4, 1 ] .
The orders of the terms of the upper central series are [ 1, 4, 32 ] .
The order of the Frattini subgroup is 4.
The exponent of G is 4.
G has a unique maximal elementary abelian subgroup which is central in G and has order 4.

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, 3, 3, 4, 4 ] , by the ideal generated by the relations
z2 + y2 + yx + x2 ,
zy + yx + x2 ,
y2x + zx2 + x3 ,
zx2 + yx2 + x3 ,
zw + yv ,
yw + zv + yv ,
yxv + x2v ,
y2u + y2t + yxt + x2t + wv ,
yxu + x2u + y2t + v2 ,
w2 + wv + v2 .

The Hilbert series for the cohomology ring is
t4+ t3+ t2+ t+ 1 / t6 -2t5+ 3t4 -4t3+ 3t2 -2t+ 1.
Its numerator factors as ( t4+t3+t2+t+1 ) .
Its denominator factors as ( t-1 )2 ( t2+1 )2 .

The Krull dimension of the cohomology ring is 2.
The cohomology ring is Cohen-Macaulay and the longest regular sequence consists of the generators
u , t .

Restriction to the Maximal Elementary Abelian Subgroup

Generated by [ G.4 * G.5, G.5 ] The cohomology ring of E is a polynomial ring in the variables z , y .

The images of the generators of the cohomology of G restricted to E are
0 ,
0 ,
0 ,
0 ,
0 ,
z4 + y4 ,
y4
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 ,
w ,
v .

This ideal is also the nilradical of the cohomology of G.

It is nilpotent of degree 5.

Restrictions to Maximal Subgroups

Maximal Subgroup H #1 Generated by [ G.1, G.2 * G.3 * G.5, G.5, G.4 ] .

The Group H 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 Generated by [ G.1, G.2 * G.3 * G.5 ] .

The images of the generators of the cohomology of G restricted to H are
z ,
y ,
y ,
zx + yx + yw ,
yx + zw ,
z2x + w2 ,
z2x + y2w + x2 + 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 #2 Generated by [ G.5, G.2, G.4, G.1 * G.3 ] .

The Group H 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 Generated by [ G.1 * G.2 * G.3 * G.4, G.1 * G.3 ] .

The images of the generators of the cohomology of G restricted to H are
z + y ,
z ,
z + y ,
zx + yw ,
zx + yx + zw ,
z2x + x2 ,
z2x + 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 #3 Generated by [ G.1, G.5, G.2, G.4 ] .

The Group H 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 Generated by [ G.1, G.2 ] .

The images of the generators of the cohomology of G restricted to H are
y ,
z ,
0 ,
zx + yx + zw ,
zx + yw ,
z2x + w2 ,
z2x + y2w + x2 + 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 #4 Generated by [ G.3, G.5, G.4, G.1 * G.2 ] .

The Group H 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 Generated by [ G.1 * G.2 * G.3 * G.5, G.1 * G.2 ] .

The images of the generators of the cohomology of G restricted to H are
z + y ,
z + y ,
z ,
zx + yx ,
zw + yw ,
x2 ,
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 #5 Generated by [ G.2 * G.3 * G.5, G.5, G.4, G.1 * G.2 ] .

The Group H 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 Generated by [ G.1 * G.3 * G.5, G.1 * G.2 ] .

The images of the generators of the cohomology of G restricted to H are
z + y ,
y ,
z ,
yx + zw ,
zx + yx + yw ,
z2x + x2 ,
z2x + x2 + 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 #6 Generated by [ G.3, G.5, G.2, G.4 ] .

The Group H 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 Generated by [ G.2 * G.3 * G.5, G.2 ] .

The images of the generators of the cohomology of G restricted to H are
0 ,
z + y ,
z ,
zw + yw ,
zx + yx ,
x2 + w2 ,
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 #7 Generated by [ G.1, G.3, G.5, G.4 ] .

The group H is abelian of type [ 4, 4 ]

The cohomology ring of H 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 G restricted to H are
z ,
0 ,
z + y ,
zx + zw ,
zw ,
w2 ,
x2
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
x3 ,
yx2 ,
y2v ,
zxv ,
x2v .

It is nilpotent of degree 2.
The annihilator of the Essential Cohomology has dimension 2 .
The essential cohomology is a free module over the polynomial subring Q of the cohomology ring of G generated by u , t .
The essential cohomology is generated as a module over Q by the elements
[] [] [ yx2, x3 ] [] [ x2v, zxv, y2v ] [ x3v ]

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 Number8 GrpPC of order 16 = 2^4 PC-Relations: $.1^2 = $.4, $.3^2 = $.4, $.3^$.2 = $.3 * $.4

of type AlmostExtraSpecial(16) .

The generators of G have images [ pcy.3, pcy.1 * pcy.2, pcy.1 ] in the quotient group.

The images of the generators of the cohomology of Q inflated to G are
z + y ,
y ,
x ,
yw + u
in the cohomology of G.

The kernel of the inflation to G of the cohomology of Q is generated by
zy + y2 + yx + x2 ,
zx2 + x3 .

Maximal Quotient Group Q #2

The kernel of the quotient is generated by G.4 * G.5 .

The Group Q 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

of type AlmostExtraSpecial(16) .

The generators of G have images [ pcy.1 * pcy.2, pcy.1 * pcy.3 * pcy.4, pcy.2 ] in the quotient group.

The images of the generators of the cohomology of Q inflated to G are
y + x ,
z + x ,
y ,
yw + yv + u + t
in the cohomology of G.

The kernel of the inflation to G of the cohomology of Q is generated by
y2 + zx ,
x3 .

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 16 Number7 GrpPC of order 16 = 2^4 PC-Relations: $.1^2 = $.4, $.2^2 = $.4, $.2^$.1 = $.2 * $.4

of type Cyclic(2) x Quaternion(8) .

The generators of G have images [ pcy.3, 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 ,
yw + t
in the cohomology of G.

The kernel of the inflation to G of the cohomology of Q is generated by
zy + yx + x2 ,
zx2 + yx2 + x3 .

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.4 * G.5
    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 ,
y ,
x ,
zyx + y2x + w ,
zyx + 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.2 * G.4
    G.3 * G.4
    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 ,
zyx + y2x + w ,
zyx + 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.4 * G.5
    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 ,
y ,
x ,
zyx + y2x + w ,
zyx + 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.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 ,
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.3 * G.4 * G.5
    G.1 * G.2 * G.3
    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
z + y ,
y ,
z + y + x ,
v ,
w ,
yw + u + t ,
yw + yv + t .

CHECKS

paramflag = true
qregflagflag = true
cmflag = true
essflag = true
centflag = true

THE COMPUTATION IS COMPLETE