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: "generalized post embedding problems"
  Abstract: The Regular Post Embedding Problem extended with partial (co)directness is shown decidable. This extends to universal and/or counting versions. It is also shown that combining directness and codirectness in Post Embedding problems leads to undecidability.

Connected through hyperedge HE-1 (induced by source paper "well quasiorders and hierarchy theory"):
  with members:
    - "on the state complexity of closures and interiors of regular languages with subwords and superwords"
    - "decidability in the logic of subsequences and supersequences"
    - "the height of piecewise testable languages with applications in logical complexity"
    - "fragments of first order logic over infinite words"

Connected through hyperedge HE-2 (induced by source paper "decidability complexity and expressiveness of first order logic over the subword ordering"):
  with members:
    - "on the state complexity of closures and interiors of regular languages with subwords and superwords"
    - "decidability in the logic of subsequences and supersequences"
    - "the height of piecewise testable languages with applications in logical complexity"
    - "subclasses of presburger arithmetic and the weak exp hierarchy"
    - "the power of priority channel systems"
    - "recompression a simple and powerful technique for word equations"

Connected through hyperedge HE-3 (induced by source paper "on reachability for unidirectional channel systems extended with regular tests"):
  with members:
    - "complexity hierarchies beyond elementary"
    - "the parametric ordinal recursive complexity of post embedding problems"
    - "graph logics with rational relations"
    - "the power of well structured systems"
    - "reachability analysis of communicating pushdown systems"
    - "cutting through regular post embedding problems"
    - "reachability of communicating timed processes"
    - "multiply recursive upper bounds with higman s lemma"

Connected through hyperedge HE-4 (induced by source paper "decidability in the logic of subsequences and supersequences"):
  with members:
    - "the power of priority channel systems"

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)