Chudnovsky, MariaSchaudt, OliverSpirkl, Sophiestein, mayaZhong, Mingxian2022-08-122022-08-122019https://doi.org/10.1007/s00453-019-00577-6http://hdl.handle.net/10012/18519This is a post-peer-review, pre-copyedit version of an article published in Algorithmica. The final authenticated version is available online at: https://doi.org/10.1007/s00453-019-00577-6It is an open problem whether the 3-coloring problem can be solved in polynomial time in the class of graphs that do not contain an induced path on t vertices, for fixed t. We propose an algorithm that, given a 3-colorable graph without an induced path on t vertices, computes a coloring with max{5,2⌈t−12⌉−2} many colors. If the input graph is triangle-free, we only need max{4,⌈t−12⌉+1} many colors. The running time of our algorithm is O((3t−2+t2)m+n) if the input graph has n vertices and m edges.engraph coloringforbidden induced pathsapproximation algorithmArticle