i1 : R = ZZ/31991[a,b,c,d] o1 = R o1 : PolynomialRing |
i2 : I = monomialCurveIdeal(R,{1,2,3})
2 2
o2 = ideal (c - b*d, b*c - a*d, b - a*c)
o2 : Ideal of R
|
i3 : M = Ext^1(I,R)
o3 = cokernel {-3} | c b a |
{-3} | d c b |
2
o3 : R-module, quotient of R
|
i4 : dim M o4 = 2 |
i5 : N = Ext^0(I,R)
o5 = image {-2} | c2-bd |
{-2} | bc-ad |
{-2} | b2-ac |
3
o5 : R-module, submodule of R
|
i6 : dim N o6 = 4 |