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: "coalgebraic characterizations of context free languages"
  Abstract: htmlabstractIn this article, we provide three coalgebraic characterizations of the class of#R##N#context-free languages, each based on the idea of adding coalgebraic structure to an existing#R##N#algebraic structure by specifying output-derivative pairs. Final coalgebra semantics then#R##N#gives an interpretation function into the nal coalgebra of all languages with the usual#R##N#output and derivative operations. The rst characterization is based on systems, where#R##N#each derivative is given as a nite language over the set of nonterminals; the second#R##N#characterization on systems where derivatives are given as elements of a term-algebra; and#R##N#the third characterization is based on adding coalgebraic structure to a class of closed#R##N#(unique) xed point expressions. We prove equivalences between these characterizations,#R##N#discuss the generalization from languages to formal power series, as well as the relationship#R##N#to the generalized powerset construction.

Connected through hyperedge HE-1 (induced by source paper "toward a uniform theory of effectful state machines"):
  with members:
    - "presenting distributive laws"
    - "towards a coalgebraic chomsky hierarchy"
    - "sound and complete axiomatizations of coalgebraic language equivalence"
    - "generalizing determinization from automata to coalgebras"
    - "reactive turing machines"
    - "non deterministic kleene coalgebras"

Connected through hyperedge HE-2 (induced by source paper "a new foundation for finitary corecursion and iterative algebras"):
  with members:
    - "proper functors and fixed points for finite behaviour"
    - "towards a coalgebraic chomsky hierarchy"
    - "sound and complete axiomatizations of coalgebraic language equivalence"
    - "generalizing determinization from automata to coalgebras"
    - "on the specification of operations on the rational behaviour of systems"
    - "semantics of higher order recursion schemes"
    - "non deterministic kleene coalgebras"
    - "the category theoretic solution of recursive program schemes"

Connected through hyperedge HE-3 (induced by source paper "stream differential equations specification formats and solution methods"):
  with members:
    - "presenting distributive laws"
    - "sound and complete axiomatizations of coalgebraic language equivalence"
    - "automatic sequences and zip specifications"
    - "well definedness of streams by transformation and termination"
    - "representations of stream processors using nested fixed points"
    - "rational streams coalgebraically"

Connected through hyperedge HE-4 (induced by source paper "companions causality and codensity"):
  with members:
    - "stream differential equations specification formats and solution methods"
    - "the largest respectful function"
    - "coinduction up to in a fibrational setting"
    - "abstract gsos rules and a modular treatment of recursive definitions"

Connected through hyperedge HE-5 (induced by source paper "towards a coalgebraic chomsky hierarchy"):
  with members:
    - "sound and complete axiomatizations of coalgebraic language equivalence"
    - "generalizing determinization from automata to coalgebras"

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)