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: "alternating automata on data trees and xpath satisfiability"
  Abstract: A data tree is an unranked ordered tree whose every node is labelled by a letter from a finite alphabet and an element ("datum") from an infinite set, where the latter can only be compared for equality. The article considers alternating automata on data trees that can move downward and rightward, and have one register for storing data. The main results are that nonemptiness over finite data trees is decidable but not primitive recursive, and that nonemptiness of safety automata is decidable but not elementary. The proofs use nondeterministic tree automata with faulty counters. Allowing upward moves, leftward moves, or two registers, each causes undecidability. As corollaries, decidability is obtained for two data-sensitive fragments of the XPath query language.

Connected through hyperedge HE-1 (induced by source paper "complexity of controlled bad sequences over finite sets of mathbb n d"):
  with members:
    - "complexity hierarchies beyond elementary"
    - "ackermannian and primitive recursive bounds with dickson s lemma"
    - "multiply recursive upper bounds with higman s lemma"

Connected through hyperedge HE-2 (induced by source paper "scalar and vectorial mu calculus with atoms"):
  with members:
    - "modal logics for nominal transition systems"
    - "reasoning about data repetitions with counter systems"
    - "smt solving for functional programming over infinite structures"
    - "automata theory in nominal sets"
    - "alternating register automata on finite words and trees"
    - "ltl with the freeze quantifier and register automata"
    - "on the freeze quantifier in constraint ltl decidability and complexity"

Connected through hyperedge HE-3 (induced by source paper "complexity hierarchies beyond elementary"):
  with members:
    - "relating timed and register automata"
    - "demystifying reachability in vector addition systems"
    - "nonelementary complexities for branching vass mell and extensions"
    - "on freeze ltl with ordered attributes"
    - "trace inclusion for one counter nets revisited"
    - "the power of priority channel systems"
    - "the parametric ordinal recursive complexity of post embedding problems"
    - "graph logics with rational relations"

Connected through hyperedge HE-4 (induced by source paper "the power of well structured systems"):
  with members:
    - "complexity hierarchies beyond elementary"
    - "the power of priority channel systems"
    - "graph logics with rational relations"
    - "parameterized verification of asynchronous shared memory systems"
    - "forward analysis for wsts part ii complete wsts"
    - "alternating register automata on finite words and trees"
    - "ackermannian and primitive recursive bounds with dickson s lemma"
    - "multiply recursive upper bounds with higman s lemma"

Connected through hyperedge HE-5 (induced by source paper "alternating register automata on finite words and trees"):
  with members:
    - "bottom up automata on data trees and vertical xpath"
    - "relating timed and register automata"
    - "ackermannian and primitive recursive bounds with dickson s lemma"
    - "ltl with the freeze quantifier and register automata"
    - "on the freeze quantifier in constraint ltl decidability and complexity"

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.LO(Logic in Computer Science)