i1 : (B,V,C) = tables(1,ZZ/33331) 2 o1 = (ideal (x , x x - x x , x x - x x , x - x x ), ideal (x - 8610x + 10298x - 14788x , x - 3956x + 10298x + 5320x - 5 2 3 1 4 1 3 0 4 1 0 2 1 2 4 5 0 2 3 4 ---------------------------------------------------------------------------------------------------------------------------- 2 2 13137x , x x - 8610x x + 10298x + 10259x x - 11729x x + 13696x x + 7509x ), ideal (x , x - 8610x + 10298x , x - 5 2 3 2 4 4 2 5 3 5 4 5 5 5 1 2 4 0 ---------------------------------------------------------------------------------------------------------------------------- 2 3956x + 10298x + 5320x , x x - 8610x x + 10298x )) 2 3 4 2 3 2 4 4 o1 : Sequence |
i2 : (?B,?V,?C) o2 = (smooth cubic surface in PP^5 cut out by 4 hypersurfaces of degrees (1,2,2,2), smooth quadric surface in PP^5, irreducible ---------------------------------------------------------------------------------------------------------------------------- conic curve in PP^5) o2 : Sequence |
i3 : B + V == C o3 = true |
The corresponding example of fourfold can be obtained as follows.
i4 : psi = rationalMap(B,Dominant=>2); o4 : RationalMap (quadratic rational map from PP^5 to 5-dimensional subvariety of PP^8) |
i5 : X = specialGushelMukaiFourfold psi V; o5 : SpecialGushelMukaiFourfold (Gushel-Mukai fourfold containing a surface of degree 2 and sectional genus 0) |
This is basically the same as doing this:
i6 : specialGushelMukaiFourfold("1",ZZ/33331); o6 : SpecialGushelMukaiFourfold (Gushel-Mukai fourfold containing a surface of degree 2 and sectional genus 0) |
The object tables is a method function.