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: "senescent ground tree rewrite systems"
  Abstract: Ground Tree Rewrite Systems with State are known to have an undecidable control state reachability problem. Taking inspiration from the recent introduction of scope-bounded multi-stack pushdown systems, we define Senescent Ground Tree Rewrite Systems. These are a restriction of ground tree rewrite systems with state such that nodes of the tree may no longer be rewritten after having witnessed an a priori fixed number of control state changes. As well as generalising scope-bounded multi-stack pushdown systems, we show --- via reductions to and from reset Petri-nets --- that these systems have an Ackermann-complete control state reachability problem. However, reachability of a regular set of trees remains undecidable.

Connected through hyperedge HE-1 (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-2 (induced by source paper "decidable models of integer manipulating programs with recursive parallelism technical report"):
  with members:
    - "context bounded analysis for concurrent programs with dynamic creation of threads"
    - "approximating petri net reachability along context free traces"

Connected through hyperedge HE-3 (induced by source paper "unboundedness and downward closures of higher order pushdown automata"):
  with members:
    - "rewriting higher order stack trees"
    - "an approach to computing downward closures"
    - "saturation of concurrent collapsible pushdown systems"

Connected through hyperedge HE-4 (induced by source paper "annotated stack trees"):
  with members:
    - "saturation of concurrent collapsible pushdown systems"
    - "symbolic reachability analysis of higher order context free processes"
    - "the complexity of games on higher order pushdown automata"

Connected through hyperedge HE-5 (induced by source paper "detecting redundant css rules in html5 applications a tree rewriting approach"):
  with members:
    - "verifying recursive active documents with positive data tree rewriting"
    - "logics for unranked trees an overview"

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)