The Traveling Salesman Problem is one of the most studied problems in computational complexity and its approximability has been a long standing open question. Currently, the best known inapproximability threshold known is \(\frac{220}{219}\) due to Papadimitriou and Vempala. Here, using an essentially different construction and also relying on the work of Berman and Karpinski on bounded occurrence CSPs, we give an alternative and simpler inapproximability proof which improves the bound to \(\frac{185}{184}\).


Travel Salesman Problem Travel Salesman Problem Optimal Tour True Edge Approximation Lower Bound 
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© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.KTH Royal Institue of TechnologySweden

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