G is the group 64gp240
The Hall-Senior number of this group is 165.
G has 4 minimal generators, rank 3 and exponent 4. The centre has rank 2.
There are 4 conjugacy classes of maximal elementary abelian subgroups. Their ranks are: 3, 3, 3, 3.
This cohomology ring calculation is complete.
Ring structure | Completion information | Koszul information | Restriction information | Poincaré series
The cohomology ring has 7 generators:
There are 6 minimal relations:
A minimal Gröbner basis for the relations ideal consists of this minimal generating set, together with the following redundant relations:
This cohomology ring was obtained from a calculation out to degree 12. The cohomology ring approximation is stable from degree 6 onwards, and Benson's tests detect stability from degree 7 onwards.
This cohomology ring has dimension 3 and depth 2. Here is a homogeneous system of parameters:
The first 2 terms h1, h2 form a regular sequence of maximum length.
The first 2 terms h1, h2 form a complete Duflot regular sequence. That is, their restrictions to the greatest central elementary abelian subgroup form a regular sequence of maximal length.
Data for Benson's test:
A basis for R/(h1, h2, h3) is as follows.
A basis for AnnR/(h1, h2)(h3) is as follows.
(1 + 4t + 7t2 + 7t3 + 5t4 + 4t5 + 3t6 + t7) / (1 - t2) (1 - t4)2