arXiv 1503.047822015-03-16math.AC

Toric rings of nonsimple polyominoes

Akihiro Shikama

英文摘要：

It is known that toric ring of a simple polyomino is ring homomorphic to a edge ring of a weakly chordal bipartite graph. In this paper we identify the toric ring of nonsimple polyominoes which are of the form "rectangle minus rectangle".

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