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 partition functions of two state spin systems"
  Abstract: Two-state spin systems is a classical topic in statistical physics. We consider the problem of computing the partition function of the systems on a bounded degree graph. Based on the self-avoiding tree, we prove the systems exhibits strong correlation decay under the condition that the absolute value of "inverse temperature" is small. Due to strong correlation decay property, an FPTAS for the partition function is presented under the same condition. This condition is sharp for Ising model.

Connected through hyperedge HE-1 (induced by source paper "sampling in uniqueness from the potts and random cluster models on random regular graphs"):
  with members:
    - "algorithms for bis hard problems on expander graphs"
    - "algorithmic pirogov sinai theory"
    - "sampling random colorings of sparse random graphs"
    - "spatial mixing and the connective constant optimal bounds"
    - "mixing of the glauber dynamics for the ferromagnetic potts model"
    - "spatial mixing and approximation algorithms for graphs with bounded connective constant"
    - "ferromagnetic potts model refined bis hardness and related results"

Connected through hyperedge HE-2 (induced by source paper "inapproximability of the partition function for the antiferromagnetic ising and hard core models"):
  with members:
    - "bis hardness for 2 spin systems on bipartite bounded degree graphs in the tree non uniqueness region"
    - "inapproximability for antiferromagnetic spin systems in the tree non uniqueness region"
    - "approximation algorithms for two state anti ferromagnetic spin systems on bounded degree graphs"
    - "correlation decay up to uniqueness in spin systems"
    - "improved inapproximability results for counting independent sets in the hard core model"
    - "computational transition at the uniqueness threshold"

Connected through hyperedge HE-3 (induced by source paper "uniqueness spatial mixing and approximation for ferromagnetic 2 spin systems"):
  with members:
    - "bis hardness for 2 spin systems on bipartite bounded degree graphs in the tree non uniqueness region"
    - "inapproximability of the partition function for the antiferromagnetic ising and hard core models"
    - "the complexity of ferromagnetic two spin systems with external fields"
    - "spatial mixing and the connective constant optimal bounds"
    - "approximation algorithms for two state anti ferromagnetic spin systems on bounded degree graphs"
    - "correlation decay up to uniqueness in spin systems"
    - "approximate counting via correlation decay in spin systems"
    - "computational transition at the uniqueness threshold"

Connected through hyperedge HE-4 (induced by source paper "on sampling from the gibbs distribution with random maximum a posteriori perturbations"):
  with members:
    - "on measure concentration of random maximum a posteriori perturbations"
    - "negative tree reweighted belief propagation"
    - "on the partition function and random maximum a posteriori perturbations"
    - "tightening lp relaxations for map using message passing"
    - "a new class of upper bounds on the log partition function"
    - "the bethe partition function of log supermodular graphical models"

Connected through hyperedge HE-5 (induced by source paper "approximation algorithms for two state anti ferromagnetic spin systems on bounded degree graphs"):
  with members:
    - "correlation decay up to uniqueness in spin systems"
    - "approximate counting via correlation decay in spin systems"
    - "improved inapproximability results for counting independent sets in the hard core model"
    - "computational transition at the uniqueness threshold"

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)