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: "a classification of symbolic transition systems"
  Abstract: We define five increasingly comprehensive classes of infinite-state systems, called STS1--5, whose state spaces have finitary structure. For four of these classes, we provide examples from hybrid systems.

Connected through hyperedge HE-1 (induced by source paper "quasipolynomial set based symbolic algorithms for parity games"):
  with members:
    - "solving parity games using an automata based algorithm"
    - "oink an implementation and evaluation of modern parity game solvers"
    - "lower bounds for symbolic computation on graphs strongly connected components liveness safety and diameter"
    - "an ordered approach to solving parity games in quasi polynomial time and quasi linear space"
    - "succinct progress measures for solving parity games"
    - "winning cores in parity games"
    - "improved algorithms for one pair and k pair streett objectives"
    - "generating and solving symbolic parity games"

Connected through hyperedge HE-2 (induced by source paper "time bounded reachability for hybrid automata complexity and fixpoints"):
  with members:
    - "on reachability for hybrid automata over bounded time"
    - "the parma polyhedra library toward a complete set of numerical abstractions for the analysis and verification of hardware and software systems"

Connected through hyperedge HE-3 (induced by source paper "multiply recursive upper bounds with higman s lemma"):
  with members:
    - "ackermannian and primitive recursive bounds with dickson s lemma"

Connected through hyperedge HE-4 (induced by source paper "generalizing the paige tarjan algorithm by abstract interpretation"):
  with members:
    - "generalized strong preservation by abstract interpretation"

Connected through hyperedge HE-5 (induced by source paper "on computing fixpoints in well structured regular model checking with applications to lossy channel systems"):
  with members:
    - "verifying nondeterministic probabilistic channel systems against ω regular linear time properties"

Connected through hyperedge HE-6 (induced by source paper "on model checking data independent systems with arrays without reset"):
  with members:
    - "verifying sequential consistency on shared memory multiprocessors by model checking"

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)