A pr 2 00 9 TORIC IDEALS GENERATED BY CIRCUITS
نویسنده
چکیده
Let IA be the toric ideal of a homogeneous normal configuration A ⊂ Z . We prove that IA is generated by circuits if and only if each unbalanced circuit of IA has a connector which is a linear combination of circuits with a square-free term. In particular, if each circuit of IA with non-square-free terms is balanced, then IA is generated by circuits. As a consequence we prove that the toric ideal of a normal edge subring of a multigraph is generated by circuits with a square-free term.
منابع مشابه
Toric Ideals Generated by Circuits
Let IA be the toric ideal of a homogeneous normal configuration A ⊂ Z . We prove that IA is generated by circuits if and only if each unbalanced circuit of IA has a “connector” which is a linear combination of circuits with a square-free term. In particular if each circuit of IA with non-square-free terms is balanced, then IA is generated by circuits. As a consequence we prove that the toric id...
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