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arXiv · 1503.06929

Graph isomorphism completeness for trapezoid graphs

Asahi Takaoka
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Abstract

The complexity of the graph isomorphism problem for trapezoid graphs has been open over a decade. This paper shows that the problem is GI-complete. More precisely, we show that the graph isomorphism problem is GI-complete for comparability graphs of partially ordered sets with interval dimension 2 and height 3. In contrast, the problem is known to be solvable in polynomial time for comparability graphs of partially ordered sets with interval dimension at most 2 and height at most 2.

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Asahi Takaoka. 2015-03-24. Graph isomorphism completeness for trapezoid graphs. https://doi.org/10.1587/transfun.e98.a.1838

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