3 – Proj | CGS

Let $G_S$ be a gram matrix of $S$.
Let $P_0$ be a known ample class.
Let $m,d$ be integers.

CGS takes this data as input and returns the set

$$\{C\in S\mid ⟨C,C{⟩}_S=d,⟨C,P_0{⟩}_S<m\}$$

When $d=-2$, the program $CGS$ acts as SmoothRationalCurves. Thus, it returns the set of classes of square $-2$ that are also classes of smooth rational curves.

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