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Schubert2 > Examples from Schubert, translated > Example from Schubert: Count the number of space conics intersecting 8 given lines

Example from Schubert: Count the number of space conics intersecting 8 given lines

> grass(3,4,d,all):
i1 : Gd = flagBundle({1,3}, VariableNames => {,"d"})

o1 = Gd

o1 : a flag bundle with subquotient ranks {1, 3}
i2 : (Sd,Qd) = bundles Gd

o2 = (Sd, Qd)

o2 : Sequence
> Proj(f,dual(symm(2,Qd)),e):
i3 : f = projectiveBundle'(dual symmetricPower_2 Qd, VariableNames => {,{e}})

o3 = f

o3 : a flag bundle with subquotient ranks {5, 1}
> integral(Gd,lowerstar(f,(2*d1+e)^8));
                                       92
i4 : integral (2*d1 + e)^8

o4 = 92