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: "the lean mathematical library"
  Abstract: This paper describes mathlib, a community-driven effort to build a unified library of mathematics formalized in the Lean proof assistant. Among proof assistant libraries, it is distinguished by its dependently typed foundations, focus on classical mathematics, extensive hierarchy of structures, use of large- and small-scale automation, and distributed organization. We explain the architecture and design decisions of the library and the social organization that has led us here.

Connected through hyperedge HE-1 (induced by source paper "sealing pointer based optimizations behind pure functions"):
  with members:
    - "tabled typeclass resolution"
    - "counting immutable beans reference counting optimized for purely functional programming"
    - "implementing and reasoning about hash consed data structures in coq"

Connected through hyperedge HE-2 (induced by source paper "normalizing casts and coercions"):
  with members:
    - "tabled typeclass resolution"
    - "a formal proof of hensel s lemma over the p adic integers"
    - "formalising perfectoid spaces"

Connected through hyperedge HE-3 (induced by source paper "validating mathematical structures"):
  with members:
    - "formalising perfectoid spaces"
    - "type classes for mathematics in type theory"

Connected through hyperedge HE-4 (induced by source paper "formalising perfectoid spaces"):
  with members:
    - "a formal proof of hensel s lemma over the p adic integers"
    - "formalizing the solution to the cap set problem"

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)