%0 Conference Proceedings %T Square, Power, Positive Closure, and Complementation on Star-Free Languages %+ School of Computer Science [Waterloo] (UWO) %+ Slovak Academy of Sciences (SAS) %A Davies, Sylvie %A Hospodár, Michal %< avec comité de lecture %( Lecture Notes in Computer Science %B 21th International Conference on Descriptional Complexity of Formal Systems (DCFS) %C Košice, Slovakia %Y Michal Hospodár %Y Galina Jirásková %Y Stavros Konstantinidis %I Springer International Publishing %3 Descriptional Complexity of Formal Systems %V LNCS-11612 %P 98-110 %8 2019-07-17 %D 2019 %R 10.1007/978-3-030-23247-4_7 %Z Computer Science [cs]Conference papers %X We examine the deterministic and nondeterministic state complexity of square, power, positive closure, and complementation on star-free languages. For the state complexity of square, we get a non-trivial upper bound $$(n-1)2^n - 2(n-2)$$ and a lower bound of order $${\Theta }(2^n)$$. For the state complexity of the k-th power in the unary case, we get the tight upper bound $$k(n-1)+1$$. Next, we show that the upper bound kn on the nondeterministic state complexity of the k-th power is met by a binary star-free language, while in the unary case, we have a lower bound $$k(n-1)+1$$. For the positive closure, we show that the deterministic upper bound $$2^{n-1}+2^{n-2}-1$$, as well as the nondeterministic upper bound n, can be met by star-free languages. We also show that in the unary case, the state complexity of positive closure is $$n^2-7n+13$$, and the nondeterministic state complexity of complementation is between $$(n-1)^2+1$$ and $$n^2-2$$. %G English %Z TC 1 %Z WG 1.02 %2 https://inria.hal.science/hal-02387295/document %2 https://inria.hal.science/hal-02387295/file/480958_1_En_7_Chapter.pdf %L hal-02387295 %U https://inria.hal.science/hal-02387295 %~ IFIP-LNCS %~ IFIP %~ IFIP-TC %~ IFIP-TC1 %~ IFIP-WG %~ IFIP-DCFS %~ IFIP-WG1-2 %~ IFIP-LNCS-11612