We also have a number of specific cases proven, which we summarize in the
following table.
For this, we introduce the following notation:
Given a Schubert condition a and a positive integer
j, (a)j
means that a is repeated j times.
Also, set Ji to be the sequence
Ji =
1, 2, ..., p-1, p+i .
The Schubert condition Ji is a Pieri-type condition,
it is the condition that a general p-plane H meet a
fixed m+1-i-plane nontrivially.
Cases Proven:
Schubert data | (J2)4 | (J2)4, J1 | (1,3,5)2, (J1)3 | (1,3,5)4 |
---|---|---|---|---|
m,p | 4,2 | 3,3 | 3,3 | 4,3 |
d | 3 | 3 | 6 | 8 |
The case (J2)4, J1 is interesting in that the discriminant is not symmetric in the 3 parameters. The case (1,3,5)2, (J1)3 is the first we showed where the conditions were not just `Pieri-type'.
The last case of (1,3,5)4 with (m,p) = (4,3)
is special.
Maple
was completely unable to handle this on its own.
The Maple
script in the link generates a
Singular
input file,
given here.
This computes a Gröbner basis, but not an eliminant, as that was also
too hard.
This Gröbner basis is stored as a
Maple V.5
file, and we have a
Maple V.5
script
that reads these equations, and (cleverly) computes the universal eliminant.
This is the first case in which the universal eliminant
factored---which suggests that the Galois group of this enumerative problem
is not the full symmetric group on 8 elements.