Small group number 9 of order 625
G is the group 625gp9
G has 2 minimal generators, rank 2 and exponent 25.
The centre has rank 1.
The 6 maximal subgroups are:
Ab(25,5), E125, M125 (4x).
There are 2 conjugacy classes of maximal
elementary abelian subgroups. Their ranks are:
2, 2.
This cohomology ring calculation is complete.
Ring structure
| Completion information
| Koszul information
| Restriction information
| Poincaré series
The cohomology ring has 23 generators:
- y1 in degree 1, a nilpotent element
- y2 in degree 1, a nilpotent element
- x1 in degree 2, a nilpotent element
- x2 in degree 2, a nilpotent element
- x3 in degree 2
- w in degree 3, a nilpotent element
- v1 in degree 4, a nilpotent element
- v2 in degree 4, a nilpotent element
- u in degree 5, a nilpotent element
- t1 in degree 6, a nilpotent element
- t2 in degree 6, a nilpotent element
- s in degree 7, a nilpotent element
- r1 in degree 8, a nilpotent element
- r2 in degree 8
- q1 in degree 9, a nilpotent element
- q2 in degree 9, a nilpotent element
- p1 in degree 10
- p2 in degree 10, a regular element
- o in degree 11, a nilpotent element
- n in degree 12
- m in degree 13, a nilpotent element
- l in degree 14
- k in degree 15, a nilpotent element
There are 230 minimal relations:
- y22 =
0
- y1.y2 =
0
- y12 =
0
- y2.x3 =
0
- y2.x2 =
- 2y1.x2
- y2.x1 =
y1.x2
- y1.x1 =
0
- x2.x3 =
0
- x1.x3 =
0
- x22 =
0
- x1.x2 =
0
- x12 =
0
- y2.w =
0
- y1.w =
0
- x3.w =
0
- x2.w =
0
- x1.w =
0
- y2.v1 =
0
- y1.v2 =
0
- y1.v1 =
0
- x3.v2 =
0
- x3.v1 =
0
- w2 =
0
- x2.v2 =
0
- x2.v1 =
0
- x1.v2 =
0
- x1.v1 =
0
- y2.u =
0
- y1.u =
0
- x3.u =
0
- w.v2 =
0
- w.v1 =
0
- x2.u =
0
- x1.u =
0
- y2.t1 =
0
- y1.t2 =
0
- y1.t1 =
0
- x3.t2 =
0
- x3.t1 =
0
- v22 =
0
- v1.v2 =
0
- v12 =
0
- w.u =
0
- x2.t2 =
0
- x2.t1 =
0
- x1.t2 =
0
- x1.t1 =
0
- y2.s =
0
- y1.s =
0
- x3.s =
0
- y1.r2 =
0
- v2.u =
0
- v1.u =
0
- w.t2 =
0
- w.t1 =
0
- x2.s =
0
- x1.s =
0
- y2.r1 =
0
- y1.r1 =
0
- x3.r2 =
2y1.q2
- x3.r1 =
- y1.q2
- x2.r2 =
y2.q1
- x1.r2 =
0
- u2 =
0
- v2.t2 =
0
- v2.t1 =
0
- v1.t2 =
0
- v1.t1 =
0
- w.s =
0
- x2.r1 =
0
- x1.r1 =
0
- y2.q2 =
2y2.q1
- y1.q1 =
0
- w.r2 =
y2.p1
- x3.q1 =
0
- y1.p1 =
0
- u.t2 =
0
- u.t1 =
0
- v2.s =
0
- v1.s =
0
- w.r1 =
0
- x2.q2 =
0
- x2.q1 =
0
- x1.q2 =
0
- x1.q1 =
0
- x3.p1 =
- 2y1.x3.q2
- v2.r2 =
2y2.o
- v1.r2 =
y2.o
- x2.p1 =
y2.o
- x1.p1 =
0
- t22 =
0
- t1.t2 =
0
- t12 =
0
- u.s =
0
- v2.r1 =
0
- v1.r1 =
0
- w.q2 =
2y2.o
- w.q1 =
y2.o
- y1.o =
- 2y1.x3.q2
- u.r2 =
y2.n
- y1.x2.p2
- w.p1 =
y2.n
- y1.x2.p2
- x3.o =
- 2x32.q2
+ y1.x3.p2
- y1.n =
- y1.x3.p2
- 2y1.x2.p2
- t2.s =
0
- t1.s =
0
- u.r1 =
0
- v2.q2 =
0
- v2.q1 =
0
- v1.q2 =
0
- v1.q1 =
0
- x2.o =
y1.x2.p2
- x1.o =
0
- x3.n =
- x32.p2
+ y1.x32.q2
- t2.r2 =
- 2y2.m
- t1.r2 =
2y2.m
- v2.p1 =
2y2.m
- v1.p1 =
y2.m
- x2.n =
y2.m
- x1.n =
0
- s2 =
0
- t2.r1 =
0
- t1.r1 =
0
- u.q2 =
2y2.m
- u.q1 =
y2.m
- w.o =
y2.m
- y1.m =
2y1.x32.q2
- s.r2 =
2y2.l
- u.p1 =
y2.l
- w.n =
y2.l
- x3.m =
2x33.q2
- y1.l =
y1.x32.p2
- s.r1 =
0
- t2.q2 =
0
- t2.q1 =
0
- t1.q2 =
0
- t1.q1 =
0
- v2.o =
0
- v1.o =
0
- x2.m =
0
- x1.m =
0
- x3.l =
x33.p2
+ 2y1.x33.q2
- r1.r2 =
- 2y2.k
- t2.p1 =
- 2y2.k
- t1.p1 =
2y2.k
- v2.n =
2y2.k
- v1.n =
y2.k
- x2.l =
y2.k
- x1.l =
0
- r12 =
0
- s.q2 =
- y2.k
- s.q1 =
2y2.k
- u.o =
y2.k
- w.m =
y2.k
- y1.k =
- y1.x33.q2
- r2.q2 =
2r2.q1
+ 2y2.r22
- s.p1 =
y2.r22
- u.n =
- 2y2.r22
- w.l =
- 2y2.r22
- x3.k =
- x34.q2
- r1.q2 =
0
- r1.q1 =
0
- t2.o =
0
- t1.o =
0
- v2.m =
0
- v1.m =
0
- x2.k =
0
- x1.k =
0
- r1.p1 =
- y2.r2.q1
- t2.n =
- y2.r2.q1
- t1.n =
y2.r2.q1
- v2.l =
y2.r2.q1
- v1.l =
- 2y2.r2.q1
- q22 =
0
- q1.q2 =
- 2y2.r2.q1
- q12 =
0
- s.o =
y2.r2.q1
- u.m =
- 2y2.r2.q1
- w.k =
- 2y2.r2.q1
- q2.p1 =
2r2.o
- y2.r2.p1
- q1.p1 =
r2.o
+ y2.r2.p1
- s.n =
y2.r2.p1
- u.l =
- 2y2.r2.p1
- r1.o =
0
- t2.m =
0
- t1.m =
0
- v2.k =
0
- v1.k =
0
- p12 =
r2.n
+ y2.r2.o
+ 2y2.q1.p2
+ 2y1.q2.p2
- r1.n =
- y2.r2.o
+ y1.q2.p2
- t2.l =
- y2.r2.o
- t1.l =
y2.r2.o
- q2.o =
- y2.r2.o
- y1.q2.p2
- q1.o =
y2.r2.o
- s.m =
y2.r2.o
- u.k =
- 2y2.r2.o
- p1.o =
r2.m
- 2y2.p1.p2
- q2.n =
2r2.m
- y2.r2.n
- x3.q2.p2
+ y2.p1.p2
- q1.n =
r2.m
+ y2.r2.n
- 2y2.p1.p2
- s.l =
y2.r2.n
- r1.m =
0
- t2.k =
0
- t1.k =
0
- p1.n =
r2.l
+ 2y2.r2.m
+ y2.p2.o
- r1.l =
- y2.r2.m
- y1.x3.q2.p2
- o2 =
0
- q2.m =
- y2.r2.m
+ y2.p2.o
- q1.m =
y2.r2.m
- 2y2.p2.o
- s.k =
y2.r2.m
- o.n =
r2.k
+ 2x32.q2.p2
+ y2.p2.n
- y1.x3.p22
+ 2y1.x2.p22
- p1.m =
r2.k
- 2y2.p2.n
+ 2y1.x2.p22
- q2.l =
2r2.k
- y2.r2.l
+ x32.q2.p2
+ 2y2.p2.n
- 2y1.x2.p22
- q1.l =
r2.k
+ y2.r2.l
+ y2.p2.n
- y1.x2.p22
- r1.k =
0
- n2 =
- 2r23
+ x32.p22
- y2.r2.k
+ y2.p2.m
- 2y1.x32.q2.p2
- p1.l =
- 2r23
- 2y2.r2.k
+ 2y2.p2.m
- 2y1.x32.q2.p2
- o.m =
- 2y2.p2.m
+ 2y1.x32.q2.p2
- q2.k =
- y2.r2.k
+ 2y2.p2.m
- q1.k =
y2.r2.k
+ y2.p2.m
- n.m =
- 2r22.q1
+ 2y2.r23
- 2x33.q2.p2
+ 2y2.p2.l
- o.l =
- 2r22.q1
+ 2y2.r23
- 2x33.q2.p2
+ y1.x32.p22
- p1.k =
- 2r22.q1
+ 2y2.r23
- y2.p2.l
- n.l =
- 2r22.p1
- x33.p22
+ y2.r22.q1
- y1.x33.q2.p2
- m2 =
0
- o.k =
y2.p2.k
- y1.x33.q2.p2
- m.l =
- 2r22.o
+ 2x34.q2.p2
+ y2.r22.p2
- n.k =
- 2r22.o
+ x34.q2.p2
+ 2y2.r22.p2
- l2 =
- 2r22.n
+ x34.p22
- 2y2.r22.o
- 2y2.r2.q1.p2
- y1.x34.q2.p2
- m.k =
- y2.r2.q1.p2
- l.k =
- 2r22.m
- x35.q2.p2
+ y2.r2.p1.p2
- k2 =
0
This minimal generating set constitutes a Gröbner
basis for the relations ideal.
Essential ideal:
There are 3 minimal generators:
Nilradical:
There are 17 minimal generators:
-
y2
-
y1
-
x2
-
x1
-
w
-
v2
-
v1
-
u
-
t2
-
t1
-
s
-
r1
-
q2
-
q1
-
o
-
m
-
k
This cohomology ring was obtained from a calculation
out to degree 30. The cohomology ring approximation
is stable from degree 30 onwards, and
Carlson's tests detect stability from degree 30
onwards.
This cohomology ring has dimension 2 and depth 1.
Here is a homogeneous system of parameters:
- h1 =
p2
in degree 10
- h2 =
r2
+ x34
in degree 8
The first
term h1 forms
a regular sequence of maximum length.
The remaining
term h2 is
annihilated by the class
x1.
The first
term h1 forms
a complete Duflot regular sequence.
That is, its restriction to the greatest central elementary abelian
subgroup forms a regular sequence of maximal length.
The ideal of essential classes is
free of rank 3 as a module over the polynomial algebra
on h1.
These free generators are:
- G1 =
y1.x2
in degree 3
- G2 =
y2.v2
in degree 5
- G3 =
y2.t2
in degree 7
The essential ideal squares to zero.
A basis for R/(h1, h2) is as follows.
Carlson's Koszul condition stipulates that this must
be confined to degrees less than 18.
-
1
in degree 0
-
y2
in degree 1
-
y1
in degree 1
-
x3
in degree 2
-
x2
in degree 2
-
x1
in degree 2
-
w
in degree 3
-
y1.x3
in degree 3
-
y1.x2
in degree 3
-
x32
in degree 4
-
v2
in degree 4
-
v1
in degree 4
-
u
in degree 5
-
y1.x32
in degree 5
-
y2.v2
in degree 5
-
x33
in degree 6
-
t2
in degree 6
-
t1
in degree 6
-
s
in degree 7
-
y1.x33
in degree 7
-
y2.t2
in degree 7
-
x34
in degree 8
-
r1
in degree 8
-
q2
in degree 9
-
q1
in degree 9
-
p1
in degree 10
-
y1.q2
in degree 10
-
o
in degree 11
-
x3.q2
in degree 11
-
n
in degree 12
-
y1.x3.q2
in degree 12
-
m
in degree 13
-
x32.q2
in degree 13
-
l
in degree 14
-
y1.x32.q2
in degree 14
-
k
in degree 15
-
x33.q2
in degree 15
-
y1.x33.q2
in degree 16
A basis for AnnR/(h1)(h2) is as follows.
Carlson's Koszul condition stipulates that this must
be confined to degrees less than 10.
-
x1
in degree 2
-
y1.x2
in degree 3
-
v2
- 2v1
in degree 4
-
y2.v2
- 2y2.v1
in degree 5
-
t2
+ t1
in degree 6
-
y2.t2
+ y2.t1
in degree 7
Restriction to maximal subgroup number 1, which is 125gp2
- y1 restricts to
0
- y2 restricts to
y1
- x1 restricts to
0
- x2 restricts to
y1.y2
- x3 restricts to
0
- w restricts to
y1.x1
- v1 restricts to
y1.y2.x1
- v2 restricts to
2y1.y2.x1
- u restricts to
y1.x12
- t1 restricts to
2y1.y2.x12
- t2 restricts to
- 2y1.y2.x12
- s restricts to
2y1.x13
- r1 restricts to
- 2y1.y2.x13
- r2 restricts to
2x14
- y1.y2.x13
- q1 restricts to
2y2.x14
- 2y1.x13.x2
- q2 restricts to
- y2.x14
+ y1.x13.x2
- y1.x14
- p1 restricts to
2x15
- 2y1.y2.x14
- p2 restricts to
- 2x25
+ 2x14.x2
+ x15
+ y1.y2.x14
- o restricts to
2y2.x15
- 2y1.x14.x2
- 2y1.x15
- n restricts to
2x16
- y1.y2.x25
+ y1.y2.x14.x2
- 2y1.y2.x15
- m restricts to
2y2.x16
+ y1.x1.x25
+ 2y1.x15.x2
- l restricts to
2x17
+ y1.y2.x1.x25
- y1.y2.x15.x2
+ 2y1.y2.x16
- k restricts to
2y2.x17
+ 2y1.x12.x25
+ y1.x16.x2
+ 2y1.x17
Restriction to maximal subgroup number 2, which is 125gp3
- y1 restricts to
y2
+ 2y1
- y2 restricts to
0
- x1 restricts to
0
- x2 restricts to
0
- x3 restricts to
2x4
+ x3
- w restricts to
0
- v1 restricts to
0
- v2 restricts to
y2.w1
- y1.w2
- u restricts to
0
- t1 restricts to
0
- t2 restricts to
w1.w2
- 2y1.x3.w2
- 2y1.x3.w1
- s restricts to
0
- r1 restricts to
- 2y2.x32.w2
- 2y1.x42.w1
+ y1.x3.x4.w1
- y1.x32.w2
+ 2y1.x32.w1
- r2 restricts to
- 2r
+ 2x3.x43
+ x33.x4
- 2y2.x32.w2
- 2y1.x42.w1
- y1.x3.x4.w1
- 2y1.x32.w1
- q1 restricts to
- y1.x3.x43
- 2y1.x32.x42
+ y1.x33.x4
+ 2y1.x34
- q2 restricts to
2x43.w1
- x3.x42.w1
- 2x32.x4.w1
+ 2x33.w2
+ x33.w1
- y1.x3.x43
- 2y1.x32.x42
+ y1.x33.x4
+ y1.x34
- p1 restricts to
- x3.x44
- 2x32.x43
+ x33.x42
+ 2x34.x4
+ y2.x33.w2
+ 2y1.x43.w1
- p2 restricts to
x3.x44
- 2x32.x43
- x33.x42
- x34.x4
- 2p
- 2y2.x33.w2
+ 2y1.x43.w1
+ y1.x3.x42.w1
- y1.x32.x4.w1
- y1.x33.w2
+ y1.x33.w1
- o restricts to
2x44.w1
+ x34.w2
- y1.x32.x43
- 2y2.p
+ y1.p
- n restricts to
- 2x33.x43
+ x34.x42
- x4.p
+ 2x3.p
- y2.x34.w2
- y1.x44.w1
+ y1.x32.x42.w1
- y1.x33.x4.w1
- y1.x34.w2
+ y1.x34.w1
- m restricts to
x45.w1
- x35.w2
+ x35.w1
+ y1.x33.x43
+ 2y1.x34.x42
+ 2y1.x35.x4
- y1.x36
- l restricts to
2x34.x43
- 2x35.x42
- 2x36.x4
+ 2x42.p
+ 2x3.x4.p
- 2x32.p
+ 2y2.x35.w2
+ y1.x33.x42.w1
- y1.x34.x4.w1
+ 2y1.x35.w2
- y1.x35.w1
- k restricts to
- x46.w1
+ x35.x4.w1
- 2x36.w2
- 2x36.w1
- 2y1.x34.x43
- 2y1.x35.x42
- y1.x37
Restriction to maximal subgroup number 3, which is 125gp4
- y1 restricts to
- 2y1
- y2 restricts to
2y1
- x1 restricts to
2y1.y2
- x2 restricts to
- 2y1.y2
- x3 restricts to
2y1.y2
- w restricts to
0
- v1 restricts to
0
- v2 restricts to
2y2.w
- u restricts to
0
- t1 restricts to
0
- t2 restricts to
- y2.u
- s restricts to
0
- r1 restricts to
0
- r2 restricts to
2x4
+ 2y2.s
- q1 restricts to
2y2.x4
- q2 restricts to
- y2.x4
- p1 restricts to
2x5
- p2 restricts to
x5
- p
+ y2.q
- o restricts to
2y2.x5
+ 2y1.p
- n restricts to
2x6
- y1.y2.p
- m restricts to
2y2.x6
- l restricts to
2x7
- k restricts to
2y2.x7
Restriction to maximal subgroup number 4, which is 125gp4
- y1 restricts to
- 2y1
- y2 restricts to
- y1
- x1 restricts to
- y1.y2
- x2 restricts to
0
- x3 restricts to
2y1.y2
- w restricts to
0
- v1 restricts to
0
- v2 restricts to
- 2y2.w
- u restricts to
0
- t1 restricts to
0
- t2 restricts to
2y2.u
- s restricts to
0
- r1 restricts to
0
- r2 restricts to
2x4
+ 2y2.s
- q1 restricts to
- y2.x4
- q2 restricts to
- 2y2.x4
- p1 restricts to
- x5
- p2 restricts to
2x5
- 2p
+ 2y2.q
- o restricts to
- 2y2.x5
- y1.p
- n restricts to
- 2x6
- 2y1.y2.p
- m restricts to
y2.x6
- l restricts to
x7
- k restricts to
2y2.x7
Restriction to maximal subgroup number 5, which is 125gp4
- y1 restricts to
- 2y1
- y2 restricts to
- 2y1
- x1 restricts to
- 2y1.y2
- x2 restricts to
y1.y2
- x3 restricts to
2y1.y2
- w restricts to
0
- v1 restricts to
0
- v2 restricts to
2y2.w
- u restricts to
0
- t1 restricts to
0
- t2 restricts to
y2.u
- s restricts to
0
- r1 restricts to
0
- r2 restricts to
2x4
+ 2y2.s
- q1 restricts to
- 2y2.x4
- q2 restricts to
y2.x4
- p1 restricts to
- 2x5
- p2 restricts to
- x5
+ p
- y2.q
- o restricts to
2y2.x5
- 2y1.p
- n restricts to
2x6
+ 2y1.y2.p
- m restricts to
- 2y2.x6
- l restricts to
- 2x7
- k restricts to
2y2.x7
Restriction to maximal subgroup number 6, which is 125gp4
- y1 restricts to
2y1
- y2 restricts to
- y1
- x1 restricts to
- y1.y2
- x2 restricts to
- y1.y2
- x3 restricts to
- 2y1.y2
- w restricts to
0
- v1 restricts to
0
- v2 restricts to
- 2y2.w
- u restricts to
0
- t1 restricts to
0
- t2 restricts to
2y2.u
- s restricts to
0
- r1 restricts to
0
- r2 restricts to
2x4
+ 2y2.s
- q1 restricts to
y2.x4
- q2 restricts to
2y2.x4
- p1 restricts to
x5
- p2 restricts to
- 2x5
- 2p
+ 2y2.q
- o restricts to
- 2y2.x5
+ y1.p
- n restricts to
- 2x6
+ y1.y2.p
- m restricts to
- y2.x6
- l restricts to
- x7
- k restricts to
2y2.x7
Restriction to maximal elementary abelian number 1, which is V25
- y1 restricts to
y2
- y2 restricts to
0
- x1 restricts to
0
- x2 restricts to
0
- x3 restricts to
x2
- w restricts to
0
- v1 restricts to
0
- v2 restricts to
0
- u restricts to
0
- t1 restricts to
0
- t2 restricts to
0
- s restricts to
0
- r1 restricts to
- 2y1.y2.x23
- r2 restricts to
- y1.y2.x23
- q1 restricts to
0
- q2 restricts to
2y2.x1.x23
- 2y1.x24
- p1 restricts to
y1.y2.x24
- p2 restricts to
- 2x1.x24
+ 2x15
- y1.y2.x24
- o restricts to
- y2.x1.x24
+ 2y2.x15
- y1.x25
- n restricts to
2x1.x25
- 2x15.x2
- 2y1.y2.x25
- m restricts to
- y2.x1.x25
+ y1.x26
- l restricts to
- 2x1.x26
+ 2x15.x22
- 2y1.y2.x26
- k restricts to
- 2y2.x1.x26
+ 2y1.x27
Restriction to maximal elementary abelian number 2, which is V25
- y1 restricts to
0
- y2 restricts to
0
- x1 restricts to
0
- x2 restricts to
0
- x3 restricts to
0
- w restricts to
0
- v1 restricts to
0
- v2 restricts to
0
- u restricts to
0
- t1 restricts to
0
- t2 restricts to
0
- s restricts to
0
- r1 restricts to
0
- r2 restricts to
2x14
- q1 restricts to
- 2y1.x14
- q2 restricts to
y1.x14
- p1 restricts to
- 2x15
- p2 restricts to
2x25
- 2x14.x2
- x15
- o restricts to
2y1.x15
- n restricts to
2x16
- m restricts to
- 2y1.x16
- l restricts to
- 2x17
- k restricts to
2y1.x17
Restriction to the greatest central elementary abelian, which is C5
- y1 restricts to
0
- y2 restricts to
0
- x1 restricts to
0
- x2 restricts to
0
- x3 restricts to
0
- w restricts to
0
- v1 restricts to
0
- v2 restricts to
0
- u restricts to
0
- t1 restricts to
0
- t2 restricts to
0
- s restricts to
0
- r1 restricts to
0
- r2 restricts to
0
- q1 restricts to
0
- q2 restricts to
0
- p1 restricts to
0
- p2 restricts to
- 2x5
- o restricts to
0
- n restricts to
0
- m restricts to
0
- l restricts to
0
- k restricts to
0
(1 + 2t + 3t2
+ 3t3 + 3t4 + 3t5
+ 3t6 + 3t7 + 2t8
+ 2t9 + t10 + t11
+ t12 + t13 + t14
+ t15 + t16) /
(1 - t8) (1 - t10)
Back to the groups of order 625