i1 : Phi = parametrize PP_(ZZ/65521)^({1,3},{2,1});
o1 : MultirationalMap (rational map from PP^4 to hypersurface in PP^2 x PP^3)
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i2 : X = image Phi;
o2 : ProjectiveVariety, hypersurface in PP^2 x PP^3
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i3 : describe X
o3 = ambient:.............. PP^2 x PP^3
dim:.................. 4
codim:................ 1
degree:............... 8
multidegree:.......... 2*T_0
generators:........... (2,0)^1
purity:............... true
dim sing. l.:......... -1
Segre embedding:...... map to PP^11
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i4 : Y = PP^{3,5};
o4 : ProjectiveVariety, PP^3 x PP^5
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i5 : Psi = Phi << Y;
o5 : MultirationalMap (rational map from PP^4 to Y)
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i6 : describe image Psi
o6 = ambient:.............. PP^3 x PP^5
dim:.................. 4
codim:................ 4
degree:............... 8
multidegree:.......... 2*T_0^2*T_1^2
generators:........... (0,1)^2 (1,0)^1 (2,0)^1
purity:............... true
dim sing. l.:......... -1
Segre embedding:...... map to PP^11 ⊂ PP^23
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