Let be a finite graph on the vertex set with the edges and the polynomial ring in variables over a field . The edge ring of is the semigroup ring which is generated by those monomials such that $e = {i, j}GK[\xb] = K[x_1, …, x_n]$ be the polynomial ring in variables over and define the surjective homomorphism $\pi : K[\xb] \to K[G]\pi(x_i) = \tb^{e_i}i = 1, …, n$. The toric ideal of is the kernel of . It will be proved that, given integers and with , there exist a finite connected nonbipartite graph on together with a reverse lexicographic order on and a lexicographic order on such that (i) is normal, (ii) and (iii) is Cohen–Macaulay, where (resp.\ ) is the initial ideal of with respect to (resp.\ ) and where $\depth K[\xb]/\ini_{<{\rev}}(I_G)K[\xb]/\ini{<_{\rev}}(I_G)$.

生成讲解博客的中文版本

生成AI智能校验的中文版本