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MatFacCurvesP4 :: candidateTablesWithIrrelevantIdealAssociated

candidateTablesWithIrrelevantIdealAssociated -- Betti candidates with pd=5 for a given shape of a matrix factorization

Synopsis

Description

The function returns a list of possible Betti tables, lying in the Boij-Soederberg cone and whose support has codimension >= 3, with the additional assumption that their projective dimension is 5. A module having a Betti table belonging to this list leads to a matrix factorization (phi,psi), if no cancellation occurs, such that one among the matrix factorizations (dual psi, dual phi), (psi, syz psi), (dual phi, syz dual phi), or (phi, psi) itself, has shape B

i1 : p=32009;
i2 : Fp=ZZ/p;
i3 : S=Fp[x_0..x_4];
i4 : beta=betti map(S^{9:0,1:-1},S^{1:-1,9:-2},0)

             0  1
o4 = total: 10 10
         0:  9  1
         1:  1  9

o4 : BettiTally
i5 : d=3;
i6 : time candidateTablesWithIrrelevantIdealAssociated(beta,d)
     -- used 4.7514 seconds

             0 1 2 3 4 5         0 1 2 3 4 5
o6 = {total: 1 4 5 5 4 1, total: 1 3 6 6 3 1}
          1: 1 4 5 . . .      1: 1 3 1 . . .
          2: . . . 5 4 1      2: . . 5 5 . .
                              3: . . . 1 3 1

o6 : List

See also

Ways to use candidateTablesWithIrrelevantIdealAssociated :