Brzozowski, JanuszLi, Baiyu2017-09-292017-09-292014-11-01http://dx.doi.org/10.1142/S0129054114400097http://hdl.handle.net/10012/12509Electronic version of an article published as International Journal of Foundations of Computer Science, 25(07), 2014, 807–821. http://dx.doi.org/10.1142/S0129054114400097 © World Scientific Publishing Company http://www.worldscientific.com/The syntactic complexity of a subclass of the class of regular languages is the maximal cardinality of syntactic semigroups of languages in that class, taken as a function of the state complexity n of these languages. We prove that n! and [e(n - 1)!] are tight upper bounds for the syntactic complexity of R- and J-trivial regular languages, respectively.enFinite automatonJ-trivialmonoidregular languageR-trivialsemigroupsyntactic complexityArticle