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: "unifying buchi complementation constructions"
  Abstract: Complementation of B\"uchi automata, required for checking automata#N#containment, is of major theoretical and practical interest in formal#N#verification. We consider two recent approaches to complementation. The first#N#is the rank-based approach of Kupferman and Vardi, which operates over a DAG#N#that embodies all runs of the automaton. This approach is based on the#N#observation that the vertices of this DAG can be ranked in a certain way,#N#termed an odd ranking, iff all runs are rejecting. The second is the#N#slice-based approach of K\"ahler and Wilke. This approach tracks levels of#N#"split trees" - run trees in which only essential information about the history#N#of each run is maintained. While the slice-based construction is conceptually#N#simple, the complementing automata it generates are exponentially larger than#N#those of the recent rank-based construction of Schewe, and it suffers from the#N#difficulty of symbolically encoding levels of split trees. In this work we#N#reformulate the slice-based approach in terms of run DAGs and preorders over#N#states. In doing so, we begin to draw parallels between the rank-based and#N#slice-based approaches. Through deeper analysis of the slice-based approach, we#N#strongly restrict the nondeterminism it generates. We are then able to employ#N#the slice-based approach to provide a new odd ranking, called a retrospective#N#ranking, that is different from the one provided by Kupferman and Vardi. This#N#new ranking allows us to construct a deterministic-in-the-limit rank-based#N#automaton with a highly restricted transition function. Further, by phrasing#N#the slice-based approach in terms of ranks, our approach affords a simple#N#symbolic encoding and achieves the tight bound of Schewe's construction

Connected through hyperedge HE-1 (induced by source paper "optimal satisfiability checking for arithmetic mu calculi"):
  with members:
    - "permutation games for the weakly aconjunctive mu calculus"
    - "satisfiability games for branching time logics"
    - "exptime tableaux for the coalgebraic mu calculus"
    - "strong completeness of coalgebraic modal logics"
    - "pspace bounds for rank 1 modal logics"
    - "decisive markov chains"

Connected through hyperedge HE-2 (induced by source paper "simulations in rank based b uchi automata complementation technical report"):
  with members:
    - "foundation for a series of efficient simulation algorithms"
    - "efficient reduction of nondeterministic automata with application to language inclusion testing"
    - "termination analysis by learning terminating programs"
    - "buchi complementation and size change termination"
    - "an efficient simulation algorithm based on abstract interpretation"

Connected through hyperedge HE-3 (induced by source paper "combinatorics of lambda terms a natural approach"):
  with members:
    - "counting and generating terms in the binary lambda calculus extended version"
    - "counting and generating lambda terms"

Connected through hyperedge HE-4 (induced by source paper "profile trees for buchi word automata with application to determinization"):
  with members:
    - "state of buchi complementation"
    - "deterministic automata for the f g fragment of ltl"
    - "b uchi complementation made tight"
    - "from nondeterministic b uchi and streett automata to deterministic parity automata"

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)