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 formalization of syntax based mathematical algorithms using quotation and evaluation"
  Abstract: Algorithms like those for differentiating functional expressions manipulate the syntactic structure of mathematical expressions in a mathematically meaningful way. A formalization of such an algorithm should include a specification of its computational behavior, a specification of its mathematical meaning, and a mechanism for applying the algorithm to actual expressions. Achieving these goals requires the ability to integrate reasoning about the syntax of the expressions with reasoning about what the expressions mean. A syntax framework is a mathematical structure that is an abstract model for a syntax reasoning system. It contains a mapping of expressions to syntactic values that represent the syntactic structures of the expressions; a language for reasoning about syntactic values; a quotation mechanism to refer to the syntactic value of an expression; and an evaluation mechanism to refer to the value of the expression represented by a syntactic value. We present and compare two approaches, based on instances of a syntax framework, to formalize a syntax-based mathematical algorithm in a formal theory T. In the first approach the syntactic values for the expressions manipulated by the algorithm are members of an inductive type in T, but quotation and evaluation are functions defined in the metatheory of T. In the second approach every expression in T is represented by a syntactic value, and quotation and evaluation are operators in T itself.

Connected through hyperedge HE-1 (induced by source paper "biform theories project description"):
  with members:
    - "hol light qe"
    - "incorporating quotation and evaluation into church s type theory"
    - "theory morphisms in church s type theory with quotation and evaluation"
    - "formalizing mathematical knowledge as a biform theory graph a case study"
    - "realms a structure for consolidating knowledge about mathematical theories"
    - "a universal machine for biform theory graphs"
    - "theory presentation combinators"
    - "the mathscheme library some preliminary experiments"

Connected through hyperedge HE-2 (induced by source paper "incorporating quotation and evaluation into church s type theory"):
  with members:
    - "hol light qe"
    - "theory morphisms in church s type theory with quotation and evaluation"
    - "formalizing mathematical knowledge as a biform theory graph a case study"
    - "modelling homogeneous generative meta programming"
    - "incorporating quotation and evaluation into church s type theory syntax and semantics"
    - "on the semantics of reflect as a basis for a reflective theorem prover"
    - "frameworks for reasoning about syntax that utilize quotation and evaluation"
    - "tactics for reasoning modulo ac in coq"

Connected through hyperedge HE-3 (induced by source paper "hol light qe"):
  with members:
    - "incorporating quotation and evaluation into church s type theory"
    - "on the semantics of intensionality and intensional recursion"
    - "formalizing mathematical knowledge as a biform theory graph a case study"
    - "incorporating quotation and evaluation into church s type theory syntax and semantics"
    - "on the semantics of reflect as a basis for a reflective theorem prover"
    - "tactics for reasoning modulo ac in coq"

Connected through hyperedge HE-4 (induced by source paper "formalizing mathematical knowledge as a biform theory graph a case study"):
  with members:
    - "incorporating quotation and evaluation into church s type theory"
    - "theory morphisms in church s type theory with quotation and evaluation"
    - "incorporating quotation and evaluation into church s type theory syntax and semantics"
    - "a scalable module system"

Connected through hyperedge HE-5 (induced by source paper "theory morphisms in church s type theory with quotation and evaluation"):
  with members:
    - "incorporating quotation and evaluation into church s type theory syntax and semantics"

Connected through hyperedge HE-6 (induced by source paper "modelling homogeneous generative meta programming"):
  with members:
    - "frameworks for reasoning about syntax that utilize quotation and evaluation"
    - "a logical foundation for environment classifiers"

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)