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: "an implementation of cad in maple utilising mccallum projection"
  Abstract: Cylindrical algebraic decomposition (CAD) is an important tool for the investigation of semi-algebraic sets. Originally introduced by Collins in the 1970s for use in quantifier elimination it has since found numerous applications within algebraic geometry and beyond. Following from his original work in 1988, McCallum presented an improved algorithm, CADW, which offered a huge increase in the practical utility of CAD. In 2009 a team based at the University of Western Ontario presented a new and quite separate algorithm for CAD, which was implemented and included in the computer algebra system Maple. As part of a wider project at Bath investigating CAD and its applications, Collins and McCallum’s CAD algorithms have been implemented in Maple. This report details these implementations and compares them to Qepcad and the Ontario algorithm. The implementations were originally undertaken to facilitate research into the connections between the algorithms. However, the ability of the code to guarantee order-invariant output has led to its use in new research on CADs which are minimal for certain problems. In addition, the implementation described here is of interest as the only full implementation of CADW, (since Qepcad does not currently make use of McCallum’s delineating polynomials), and hence can solve problems not admissible to other CAD implementations.

Connected through hyperedge HE-1 (induced by source paper "truth table invariant cylindrical algebraic decomposition"):
  with members:
    - "improving the use of equational constraints in cylindrical algebraic decomposition"
    - "truth table invariant cylindrical algebraic decomposition by regular chains"
    - "applying machine learning to the problem of choosing a heuristic to select the variable ordering for cylindrical algebraic decomposition"
    - "choosing a variable ordering for truth table invariant cylindrical algebraic decomposition by incremental triangular decomposition"
    - "cylindrical algebraic decomposition using local projections"
    - "using the distribution of cells by dimension in a cylindrical algebraic decomposition"
    - "problem formulation for truth table invariant cylindrical algebraic decomposition by incremental triangular decomposition"
    - "using the regular chains library to build cylindrical algebraic decompositions by projecting and lifting"

Connected through hyperedge HE-2 (induced by source paper "an implementation of sub cad in maple"):
  with members:
    - "truth table invariant cylindrical algebraic decomposition"
    - "truth table invariant cylindrical algebraic decomposition by regular chains"
    - "using the distribution of cells by dimension in a cylindrical algebraic decomposition"
    - "problem formulation for truth table invariant cylindrical algebraic decomposition by incremental triangular decomposition"
    - "using the regular chains library to build cylindrical algebraic decompositions by projecting and lifting"
    - "cylindrical algebraic sub decompositions"
    - "an implementation of cad in maple utilising problem formulation equational constraints and truth table invariance"
    - "cylindrical algebraic decompositions for boolean combinations"

Connected through hyperedge HE-3 (induced by source paper "using the regular chains library to build cylindrical algebraic decompositions by projecting and lifting"):
  with members:
    - "truth table invariant cylindrical algebraic decomposition"
    - "truth table invariant cylindrical algebraic decomposition by regular chains"
    - "problem formulation for truth table invariant cylindrical algebraic decomposition by incremental triangular decomposition"
    - "cylindrical algebraic sub decompositions"
    - "understanding branch cuts of expressions"
    - "an implementation of cad in maple utilising problem formulation equational constraints and truth table invariance"
    - "cylindrical algebraic decompositions for boolean combinations"
    - "optimising problem formulation for cylindrical algebraic decomposition"

Connected through hyperedge HE-4 (induced by source paper "cylindrical algebraic sub decompositions"):
  with members:
    - "truth table invariant cylindrical algebraic decomposition"
    - "understanding branch cuts of expressions"
    - "applications of continuous amortization to bisection based root isolation"
    - "an implementation of cad in maple utilising problem formulation equational constraints and truth table invariance"
    - "cylindrical algebraic decompositions for boolean combinations"
    - "optimising problem formulation for cylindrical algebraic decomposition"
    - "a piano movers problem reformulated"
    - "an incremental algorithm for computing cylindrical algebraic decompositions"

Connected through hyperedge HE-5 (induced by source paper "a piano movers problem reformulated"):
  with members:
    - "cylindrical algebraic sub decompositions"
    - "an implementation of cad in maple utilising problem formulation equational constraints and truth table invariance"
    - "cylindrical algebraic decompositions for boolean combinations"
    - "optimising problem formulation for cylindrical algebraic decomposition"
    - "program verification in the presence of complex numbers functions with branch cuts etc"
    - "computing cylindrical algebraic decomposition via triangular decomposition"

Connected through hyperedge HE-6 (induced by source paper "optimising problem formulation for cylindrical algebraic decomposition"):
  with members:
    - "understanding branch cuts of expressions"
    - "cylindrical algebraic decompositions for boolean combinations"
    - "a bi directional refinement algorithm for the calculus of co inductive constructions"
    - "program verification in the presence of complex numbers functions with branch cuts etc"
    - "computing cylindrical algebraic decomposition via triangular decomposition"

Connected through hyperedge HE-7 (induced by source paper "an implementation of cad in maple utilising problem formulation equational constraints and truth table invariance"):
  with members:
    - "cylindrical algebraic decompositions for boolean combinations"
    - "optimising problem formulation for cylindrical algebraic decomposition"
    - "program verification in the presence of complex numbers functions with branch cuts etc"
    - "computing cylindrical algebraic decomposition via triangular decomposition"

Connected through hyperedge HE-8 (induced by source paper "cylindrical algebraic decompositions for boolean combinations"):
  with members:
    - "optimising problem formulation for cylindrical algebraic decomposition"
    - "program verification in the presence of complex numbers functions with branch cuts etc"
    - "computing cylindrical algebraic decomposition via triangular decomposition"

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.SC(Symbolic Computation)