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 distribution of loop lengths in graphical models for turbo decoding"
  Abstract: This correspondence analyzes the distribution of loop lengths in graphical models for turbo decoding. The properties of such loops are of significant interest in the context of iterative decoding algorithms based on belief propagation. We estimate the probability that there exist no loops of length less than or equal to c at a randomly chosen node in the acyclic directed graphical (ADC) model for turbo decoding, using a combination of counting arguments and approximations. When K, the number of information bits, is large, this probability is approximately e -2/sup c-1/-4/K, for c/spl ges/4, where nodes for input information bits are ignored for convenience. The analytical results are validated by simulations. For example, for turbo codes with K=64,000, a randomly chosen node has a less than 1% chance of being on a loop of length less than or equal to 10, but has a greater than 99.9% chance of being on a loop of length less than or equal to 20.

Connected through hyperedge HE-1 (induced by source paper "the extraction and complexity limits of graphical models for linear codes"):
  with members:
    - "on minimal tree realizations of linear codes"
    - "a decomposition theory for binary linear codes"
    - "conditionally cycle free generalized tanner graphs theory and application to high rate serially concatenated codes"
    - "graph cover decoding and finite length analysis of message passing iterative decoding of ldpc codes"
    - "capacity achieving ensembles for the binary erasure channel with bounded complexity"

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)