human: Given a node-centered hypergraph: <hypergraph>, where nodes represent papers and hyperedges represent sets of papers co-cited by a source paper.

Details of the hypergraph:
Center node: "most complex regular right ideal languages"
  Abstract: A right ideal is a language L over an alphabet A that satisfies L = LA*. We show that there exists a stream (sequence) (R_n : n \ge 3) of regular right ideal languages, where R_n has n left quotients and is most complex under the following measures of complexity: the state complexities of the left quotients, the number of atoms (intersections of complemented and uncomplemented left quotients), the state complexities of the atoms, the size of the syntactic semigroup, the state complexities of the operations of reversal, star, and product, and the state complexities of all binary boolean operations. In that sense, this stream of right ideals is a universal witness.

Connected through hyperedge HE-1 (induced by source paper "complexity of suffix free regular languages"):
  with members:
    - "complexity of proper suffix convex regular languages"
    - "most complex non returning regular languages"
    - "unrestricted state complexity of binary operations on regular languages"
    - "complexity of prefix convex regular languages"
    - "syntactic complexity of bifix free languages"
    - "quotient complexities of atoms in regular ideal languages"
    - "upper bounds on syntactic complexity of left and two sided ideals"
    - "complexity of atoms combinatorially"

Connected through hyperedge HE-2 (induced by source paper "a survey on operational state complexity"):
  with members:
    - "maximally atomic languages"
    - "upper bounds on syntactic complexity of left and two sided ideals"
    - "syntactic complexity of r and j trivial regular languages"
    - "the state complexity of star complement star"
    - "quotient complexity of star free languages"
    - "the magic number problem for subregular language families"
    - "nondeterministic state complexity for suffix free regular languages"
    - "quotient complexity of ideal languages"

Connected through hyperedge HE-3 (induced by source paper "symmetric groups and quotient complexity of boolean operations"):
  with members:
    - "maximally atomic languages"
    - "universal witnesses for state complexity of basic operations combined with reversal"
    - "quotient complexities of atoms of regular languages"
    - "theory of atomata"
    - "quotient complexity of ideal languages"
    - "quotient complexity of regular languages"

Question: Please tell me which class the center node belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.FL(Formal Languages and Automata Theory)