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UnirationalComponentOf6GonalGenus11Curves :: random6gonalGenus11Curve10Pencil

random6gonalGenus11Curve10Pencil

Synopsis

Description

The function gives a plane curve of degree 8 with 10 ordinary double points, such that the pencils of lines through each double points cut out 10 pencils on its canonical model, and results in the Betti number B(5,6)=50.

i1 : p=101;
i2 : (G,Ican)=random6gonalGenus11Curve10Pencil(p);
i3 : genus Ican, degree Ican

o3 = (11, 20)

o3 : Sequence
i4 : Fres=res(Ican, FastNonminimal => true);
i5 : betti(Fres, Minimize=>true)

            0  1   2   3   4   5   6   7  8 9
o5 = total: 1 36 160 315 338 338 315 160 36 1
         0: 1  .   .   .   .   .   .   .  . .
         1: . 36 160 315 288  50   .   .  . .
         2: .  .   .   .  50 288 315 160 36 .
         3: .  .   .   .   .   .   .   .  . 1

o5 : BettiTally

Ways to use random6gonalGenus11Curve10Pencil :