> grass(3,6,c):
i1 : Gc = flagBundle({3,3}, VariableNames => {,c})
o1 = Gc
o1 : a flag bundle with subquotient ranks {2:3}
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i2 : (Sc,Qc) = bundles Gc
o2 = (Sc, Qc)
o2 : Sequence
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> B:=Symm(3,Qc):
i3 : B = symmetricPower_3 Qc
o3 = B
o3 : an abstract sheaf of rank 10 on Gc
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> Proj(X,dual(B),z):
i4 : X = projectiveBundle'(dual B, VariableNames => {,{z}})
o4 = X
o4 : a flag bundle with subquotient ranks {9, 1}
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> A:=Symm(6,Qc)-Symm(3,Qc)&@o(-z):
i5 : A = symmetricPower_6 Qc - symmetricPower_3 Qc ** OO(-z)
o5 = A
o5 : an abstract sheaf of rank 18 on X
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> c18:=chern(rank(A),A):
> lowerstar(X,c18):
> integral(Gc,%);
Ans = 2734099200
i6 : integral chern A
o6 = 2734099200
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