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: "inapproximability of the partition function for the antiferromagnetic ising and hard core models"
  Abstract: Recent inapproximability results of Sly ( 2010 ), together with an approximation algorithm presented by Weitz ( 2006 ), establish a beautiful picture of the computational complexity of approximating the partition function of the hard-core model. Let λ #N#                       c #N#                    ( #N#                       #N#                          #N#                         #N#            #N#             #N#                 #N#                    $\mathbb{T}_{\Delta}$#N#                 #N#             #N#        #N#                       #N#                    ) denote the critical activity for the hard-model on the infinite Δ-regular tree. Weitz presented an  FPTAS  for the partition function when λ  #N#                       c #N#                    ( #N#                       #N#                          #N#                         #N#            #N#             #N#                 #N#                    $\mathbb{T}_{\Delta}$#N#                 #N#             #N#        #N#                       #N#                    ) for graphs with constant maximum degree Δ. In contrast, Sly showed that for all Δ ⩾ 3, there exists e Δ  > 0 such that (unless RP = NP) there is no  FPRAS  for approximating the partition function on graphs of maximum degree Δ for activities λ satisfying λ #N#                       c #N#                    ( #N#                       #N#                          #N#                         #N#            #N#             #N#                 #N#                    $\mathbb{T}_{\Delta}$#N#                 #N#             #N#        #N#                       #N#                    )  #N#                       c #N#                    ( #N#                       #N#                          #N#                         #N#            #N#             #N#                 #N#                    $\mathbb{T}_{\Delta}$#N#                 #N#             #N#        #N#                       #N#                    ) + e Δ . #N#                 We prove that a similar phenomenon holds for the antiferromagnetic Ising model. Sinclair, Srivastava and Thurley ( 2014 ) extended Weitz's approach to the antiferromagnetic Ising model, yielding an  FPTAS  for the partition function for all graphs of constant maximum degree Δ when the parameters of the model lie in the uniqueness region of the infinite Δ-regular tree. We prove the complementary result for the antiferromagnetic Ising model without external field, namely, that unless RP = NP, for all Δ ⩾ 3, there is no  FPRAS  for approximating the partition function on graphs of maximum degree Δ when the inverse temperature lies in the non-uniqueness region of the infinite tree  #N#                       #N#                          #N#                         #N#            #N#             #N#                 #N#                    $\mathbb{T}_{\Delta}$#N#                 #N#             #N#        #N#                       #N#                    . Our proof works by relating certain second moment calculations for random Δ-regular bipartite graphs to the tree recursions used to establish the critical points on the infinite tree.

Connected through hyperedge HE-1 (induced by source paper "lower bounds for testing graphical models colorings and antiferromagnetic ising models"):
  with members:
    - "approximating pairwise correlations in the ising model"
    - "learning graphical models using multiplicative weights"
    - "sample optimal identity testing with high probability"
    - "structure learning of h colorings"
    - "a new approach for testing properties of discrete distributions"
    - "testing ising models"
    - "bis hardness for 2 spin systems on bipartite bounded degree graphs in the tree non uniqueness region"
    - "random cluster dynamics for the ising model is rapidly mixing"

Connected through hyperedge HE-2 (induced by source paper "counting independent sets and colorings on random regular bipartite graphs"):
  with members:
    - "algorithms for bis hard problems on expander graphs"
    - "improved bounds for randomly sampling colorings via linear programming"
    - "bis hardness for 2 spin systems on bipartite bounded degree graphs in the tree non uniqueness region"
    - "an fptas for counting proper four colorings on cubic graphs"
    - "fptas for bis with degree bounds on one side"
    - "the expressibility of functions on the boolean domain with applications to counting csps"
    - "ferromagnetic potts model refined bis hardness and related results"
    - "approximating the partition function of the ferromagnetic potts model"

Connected through hyperedge HE-3 (induced by source paper "perfect sampling from spatial mixing"):
  with members:
    - "dynamic sampling from graphical models"
    - "on local distributed sampling and counting"
    - "approximately counting bases of bicircular matroids"
    - "improved bounds for randomly sampling colorings via linear programming"
    - "a polynomial time approximation algorithm for all terminal network reliability"
    - "approximate counting via correlation decay on planar graphs"
    - "approximation algorithms for two state anti ferromagnetic spin systems on bounded degree graphs"
    - "correlation decay up to uniqueness in spin systems"

Connected through hyperedge HE-4 (induced by source paper "markov chains for the hard core model via polymer models"):
  with members:
    - "counting independent sets and colorings on random regular bipartite graphs"
    - "algorithms for bis hard problems on expander graphs"
    - "algorithmic pirogov sinai theory"
    - "bis hardness for 2 spin systems on bipartite bounded degree graphs in the tree non uniqueness region"
    - "fptas for bis with degree bounds on one side"
    - "computational transition at the uniqueness threshold"

Connected through hyperedge HE-5 (induced by source paper "zeros of ferromagnetic 2 spin systems"):
  with members:
    - "zeros of holant problems locations and algorithms"
    - "the ising partition function zeros and deterministic approximation"
    - "uniqueness spatial mixing and approximation for ferromagnetic 2 spin systems"
    - "approximation algorithms for two state anti ferromagnetic spin systems on bounded degree graphs"
    - "correlation decay up to uniqueness in spin systems"

Connected through hyperedge HE-6 (induced by source paper "dynamic mcmc sampling"):
  with members:
    - "uniform sampling through the lov asz local lemma"
    - "convergence of mcmc and loopy bp in the tree uniqueness region for the hard core model"
    - "correlation decay up to uniqueness in spin systems"

Connected through hyperedge HE-7 (induced by source paper "dynamic sampling from graphical models"):
  with members:
    - "distributed symmetry breaking in sampling optimal distributed randomly coloring with fewer colors"
    - "a simple parallel and distributed sampling technique local glauber dynamics"
    - "tight bounds for popping algorithms"
    - "sublogarithmic distributed algorithms for lov asz local lemma and the complexity hierarchy"
    - "what can be sampled locally"
    - "a polynomial time approximation algorithm for all terminal network reliability"
    - "uniform sampling through the lov asz local lemma"
    - "convergence of mcmc and loopy bp in the tree uniqueness region for the hard core model"

Connected through hyperedge HE-8 (induced by source paper "algorithms for bis hard problems on expander graphs"):
  with members:
    - "markov chains for the hard core model via polymer models"
    - "counting independent sets and colorings on random regular bipartite graphs"
    - "sampling in uniqueness from the potts and random cluster models on random regular graphs"
    - "algorithmic pirogov sinai theory"
    - "bis hardness for 2 spin systems on bipartite bounded degree graphs in the tree non uniqueness region"
    - "convergence of mcmc and loopy bp in the tree uniqueness region for the hard core model"
    - "random cluster dynamics for the ising model is rapidly mixing"
    - "fptas for bis with degree bounds on one side"

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)