We show that there is no time algorithm for Independent Set on -vertex graphs with rank-width , unless the Exponential Time Hypothesis (ETH) fails. Our lower bound matches the time algorithm given by Bui-Xuan, Telle, and Vatshelle [Discret. Appl. Math., 2010] and it answers the open question of Bergougnoux and Kanté [SIAM J. Discret. Math., 2021]. We also show that the known time algorithms for Weighted Dominating Set, Maximum Induced Matching and Feedback Vertex Set parameterized by rank-width are optimal assuming ETH. Our results are the first tight ETH lower bounds parameterized by rank-width that do not follow directly from lower bounds for -vertex graphs.
This is a joint work with Tuukka Korhonen and Jesper Nederlof.
Accepted to STACS 2023 and available on arXiv https://arxiv.org/abs/2210.02117