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: "complexity bounds for ordinal based termination"
  Abstract: `What more than its truth do we know if we have a proof of a theorem in a given formal system?' We examine Kreisel's question in the particular context of program termination proofs, with an eye to deriving complexity bounds on program running times. #R##N#Our main tool for this are length function theorems, which provide complexity bounds on the use of well quasi orders. We illustrate how to prove such theorems in the simple yet until now untreated case of ordinals. We show how to apply this new theorem to derive complexity bounds on programs when they are proven to terminate thanks to a ranking function into some ordinal.

Connected through hyperedge HE-1 (induced by source paper "the ideal approach to computing closed subsets in well quasi orderings"):
  with members:
    - "mixed powerdomains for probability and nondeterminism"
    - "well behaved transition systems"
    - "complexity hierarchies beyond elementary"
    - "demystifying reachability in vector addition systems"
    - "finite automata for the sub and superword closure of cfls descriptional and computational complexity"
    - "the power of priority channel systems"
    - "computing downward closures for stacked counter automata"
    - "the power of well structured systems"

Connected through hyperedge HE-2 (induced by source paper "reachability is tower complete"):
  with members:
    - "reachability in vector addition systems is primitive recursive in fixed dimension"
    - "the reachability problem for petri nets is not elementary"
    - "complexity hierarchies beyond elementary"
    - "reachability in two dimensional unary vector addition systems with states is nl complete"
    - "reachability in two dimensional vector addition systems with states is pspace complete"
    - "the general vector addition system reachability problem by presburger inductive invariants"

Connected through hyperedge HE-3 (induced by source paper "reachability in vector addition systems is primitive recursive in fixed dimension"):
  with members:
    - "the reachability problem for petri nets is not elementary"
    - "vass reachability in three steps"
    - "unboundedness problems for languages of vector addition systems"
    - "on the upward downward closures of petri nets"
    - "the complexity of downward closure comparisons"
    - "complexity hierarchies beyond elementary"
    - "reachability in two dimensional unary vector addition systems with states is nl complete"
    - "demystifying reachability in vector addition systems"

Connected through hyperedge HE-4 (induced by source paper "bisimulation equivalence of first order grammars is ackermann complete"):
  with members:
    - "equivalence of pushdown automata via first order grammars"
    - "complexity hierarchies beyond elementary"
    - "branching bisimilarity checking for prs"
    - "bisimulation equivalence of first order grammars"
    - "bpa bisimilarity is exptime hard"
    - "beyond language equivalence on visibly pushdown automata"
    - "the bisimulation problem for equational graphs of finite out degree"

Connected through hyperedge HE-5 (induced by source paper "demystifying reachability in vector addition systems"):
  with members:
    - "reasoning about data repetitions with counter systems"
    - "complexity hierarchies beyond elementary"
    - "reachability in two dimensional vector addition systems with states is pspace complete"
    - "an approach to computing downward closures"
    - "the reachability problem for vector addition systems with a stack is not elementary"
    - "algorithmic verification of asynchronous programs"
    - "ackermannian and primitive recursive bounds with dickson s lemma"
    - "on selective unboundedness of vass"

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)