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: "approximating the satisfiability threshold for random k xor formulas"
  Abstract: In this paper we study random linear systems with $k$ variables per equation over the finite field GF(2), or equivalently $k$-XOR-CNF formulas. In a previous paper Creignou and Daud\'e proved that the phase transition for the consistency (satisfiability) of such systems (formulas) exhibits a sharp threshold. Here we prove that the phase transition occurs as the number of equations (clauses) is proportional to the number of variables. For any $k\ge 3$ we establish first estimates for the critical ratio. For $k=3$ we get 0.93 as an upper bound, 0.89 as a lower bound, whereas experiments suggest that the critical ratio is approximately 0.92.

Connected through hyperedge HE-1 (induced by source paper "lower bounds on the rate distortion function of ldgm codes"):
  with members:
    - "lower bounds on the rate distortion function of individual ldgm codes"
    - "binary quantization using belief propagation with decimation over factor graphs of ldgm codes"
    - "analysis of ldgm and compound codes for lossy compression and binning"
    - "low density codes achieve the rate distortion bound"
    - "low density constructions can achieve the wyner ziv and gelfand pinsker bounds"
    - "iterative quantization using codes on graphs"

Connected through hyperedge HE-2 (induced by source paper "low density graph codes that are optimal for source channel coding and binning"):
  with members:
    - "analysis of ldgm and compound codes for lossy compression and binning"
    - "low density codes achieve the rate distortion bound"
    - "low density constructions can achieve the wyner ziv and gelfand pinsker bounds"
    - "capacity achieving ensembles for the binary erasure channel with bounded complexity"
    - "lossy source encoding via message passing and decimation over generalized codewords of ldgm codes"
    - "iterative quantization using codes on graphs"

Connected through hyperedge HE-3 (induced by source paper "phase transition for random quantified xor formulas"):
  with members:
    - "typical random 3 sat formulae and the satisfiability threshold"

Connected through hyperedge HE-4 (induced by source paper "analysis of ldgm and compound codes for lossy compression and binning"):
  with members:
    - "lossy source encoding via message passing and decimation over generalized codewords of ldgm codes"
    - "iterative quantization using codes on graphs"

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.DM(Discrete Mathematics)