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: "algebraic semantics for a modal logic close to s1"
  Abstract: The modal systems S1--S3 were introduced by C. I. Lewis as logics for strict implication. While there are Kripke semantics for S2 and S3, there is no known natural semantics for S1. We extend S1 by a Substitution Principle SP which generalizes a reference rule of S1. In system S1+SP, the relation of strict equivalence $\varphi\equiv\psi$ satisfies the identity axioms of R. Suszko's non-Fregean logic adapted to the language of modal logic (we call these axioms the axioms of propositional identity). This enables us to develop a framework of algebraic semantics which captures S1+SP as well as the Lewis systems S3--S5. So from the viewpoint of algebraic semantics, S1+SP turns out to be an interesting modal logic. We show that S1+SP is strictly contained between S1 and S3 and differs from S2. It is the weakest modal logic containing S1 such that strict equivalence is axiomatized by propositional identity.

Connected through hyperedge HE-1 (induced by source paper "reasoning about proof and knowledge"):
  with members:
    - "epistemic extensions of combined classical and intuitionistic propositional logic"
    - "a modal logic amalgam of classical and intuitionistic propositional logic"
    - "denotational semantics for modal systems s3 s5 extended by axioms for propositional quantifiers and identity"

Connected through hyperedge HE-2 (induced by source paper "epistemic extensions of combined classical and intuitionistic propositional logic"):
  with members:
    - "a modal logic amalgam of classical and intuitionistic propositional logic"
    - "denotational semantics for modal systems s3 s5 extended by axioms for propositional quantifiers and identity"

Connected through hyperedge HE-3 (induced by source paper "a modal logic amalgam of classical and intuitionistic propositional logic"):
  with members:
    - "denotational semantics for modal systems s3 s5 extended by axioms for propositional quantifiers and identity"

Connected through hyperedge HE-4 (induced by source paper "combining intermediate propositional logics with classical logic"):
  with members:
    - "a modal logic amalgam of classical and intuitionistic propositional logic"
    - "characterization of strongly equivalent logic programs in intermediate logics"

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)