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MatFac15 :: constructEx5

constructEx5 -- randomly choose a module N with Betti table as indicated in o4 below

Synopsis

Description

We follow the random construction of an element of the family from Thm 4.7 or Thm 4.8 as explained in Matrix factorizations and families of curves of genus 15

i1 : kk=ZZ/10007;S=kk[x_0..x_4];
i3 : N=constructEx5(S);
i4 : betti res N

            0  1  2 3
o4 = total: 6 13 12 5
         3: 6 11  . .
         4: .  2 12 4
         5: .  .  . 1

o4 : BettiTally
i5 : E=annihilator N; (degree E,genus E)==(14,15)

o5 : Ideal of S

o6 = true
i7 : (M0,M1)=matrixFactorizationFromModule(N);
i8 : tangentKernelDimension(N,M0)==6

o8 = true
i9 : betti res annihilator N

            0 1  2 3
o9 = total: 1 6 10 5
         0: 1 .  . .
         1: . 1  . .
         2: . 2  . .
         3: . 3 10 5

o9 : BettiTally
i10 : N=constructEx5(S,{(4,1)});
i11 : betti res N

             0  1  2 3
o11 = total: 6 13 12 5
          3: 6 11  . .
          4: .  2 12 4
          5: .  .  . 1

o11 : BettiTally
i12 : E=annihilator N; (degree E,genus E)==(14,16)

o12 : Ideal of S

o13 = true
i14 : (M0,M1)=matrixFactorizationFromModule(N);
i15 : tangentKernelDimension(N,M0)==10

o15 = true
i16 : betti res annihilator N

             0 1 2 3
o16 = total: 1 4 5 2
          0: 1 . . .
          1: . 1 . .
          2: . 3 1 .
          3: . . 4 1
          4: . . . 1

o16 : BettiTally
i17 : N=constructEx5(S,14);
i18 : betti res N

             0  1  2 3
o18 = total: 5 12 13 6
          0: 1  .  . .
          1: 4 12  2 .
          2: .  . 11 6

o18 : BettiTally
i19 : E=annihilator N; (degree E,genus E)==(14,14)

o19 : Ideal of S

o20 = true
i21 : (M0,M1)=matrixFactorizationFromModule(N);
i22 : tangentKernelDimension(N,M0)==4

o22 = true
i23 : betti res annihilator N

             0 1 2 3
o23 = total: 1 6 9 4
          0: 1 . . .
          1: . . . .
          2: . 6 3 .
          3: . . 6 4

o23 : BettiTally

Ways to use constructEx5 :

  • constructEx5(PolynomialRing)
  • constructEx5(PolynomialRing,List)
  • constructEx5(PolynomialRing,ZZ)