This uses the edge ideal notion of Cohen-Macaulayness; a hypergraph is called C-M if and only if its edge ideal is C-M.
i1 : R = QQ[a..e]; |
i2 : C = cycle R; |
i3 : UnmixedTree = graph {a*b, b*c, c*d}; |
i4 : MixedTree = graph {a*b, a*c, a*d}; |
i5 : isCM C o5 = true |
i6 : isCM UnmixedTree o6 = true |
i7 : isCM MixedTree o7 = false |
The object isCM is a method function.