The integer nu needs to be a good degree for the first parameter {f0,f1,f2,f3} that can be verified by doing isGoodDegree(polinomialList,nu).
isGoodDegree verifies if the approximation complex Z associated to the polynomials given is acyclic in degree nu.
Given a list of polynomials {f0,f1,f2,f3}, the approximation complex of cycles is bigraded. This funtion verifies if the strand of degree 'nu' is acyclic.
Precisely, it computes the Euler characteristic of the nu-strand of the Z-complex, by computing the alternate sum of (-1)^i * hilbertFunction(nu+i*d,Z_i).
Note: the polynomials must be the inhomogeneous polynomials defining the affine parametrization.
i1 : S = QQ[s,t];
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i2 : f0 = s^2+s^3*t;
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i3 : f1 = s^3*t^6+1;
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i4 : f2 = s*t^2+2*s^3*t^5;
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i5 : f3 = s^2+s^3*t^6;
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i6 : l = {f0,f1,f2,f3};
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i7 : isGoodDegree (l,2)
o7 = true
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