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: "set theory for verification i from foundations to functions"
  Abstract: A logic for specification and verification is derived from the axioms of Zermelo-Fraenkel set theory. The proofs are performed using the proof assistant Isabelle. Isabelle is generic, supporting several different logics. Isabelle has the flexibility to adapt to variants of set theory. Its higher-order syntax supports the definition of new binding operators. Unknowns in subgoals can be instantiated incrementally. The paper describes the derivation of rules for descriptions, relations and functions, and discusses interactive proofs of Cantor's Theorem, the Composition of Homomorphisms challenge [9], and Ramsey's Theorem [5]. A generic proof assistant can stand up against provers dedicated to particular logics.

Connected through hyperedge HE-1 (induced by source paper "formalization of the fundamental group in untyped set theory using auto2"):
  with members:
    - "auto2 a saturation based heuristic prover for higher order logic"
    - "set theory for verification ii induction and recursion"

Connected through hyperedge HE-2 (induced by source paper "foundational extensible corecursion"):
  with members:
    - "programming and reasoning with guarded recursion for coinductive types"
    - "co recursion in logic programming lazy vs eager"
    - "abstract gsos rules and a modular treatment of recursive definitions"
    - "parametricity in an impredicative sort"
    - "miniagda integrating sized and dependent types"
    - "a formally verified compiler back end"
    - "set theory for verification ii induction and recursion"

Connected through hyperedge HE-3 (induced by source paper "set theory or higher order logic to represent auction concepts in isabelle"):
  with members:
    - "proving soundness of combinatorial vickrey auctions and generating verified executable code"
    - "the formare project formal mathematical reasoning in economics"
    - "a qualitative comparison of the suitability of four theorem provers for basic auction theory"
    - "defining functions on equivalence classes"

Connected through hyperedge HE-4 (induced by source paper "set theory for verification ii induction and recursion"):
  with members:
    - "constructing recursion operators in intuitionistic type theory"

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)