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: "separating an r outerplanar graph into gluable pieces"
  Abstract: Let G be an r-outerplanar graph with n vertices. We provide a sequence of log(n)/(r+1)^(32r^2 +8r) separators in G, each containing a fixed number (at most 2r) of integer- labeled vertices and each separating the graph in a well-defined left and right side such that the following two conditions are fulfilled. (1) The separators are nested, meaning that the left side of every separator S is contained in all the left sides of separators followin S. (2) For each pair of separators, glueing the left side of the first and the right side of the second separator results in an r-outerplanar graph. Herein, gluing means to take the disjoint union and identify the vertices in the separators with the same labels. #R##N#We apply the sequences as above to the problem of finding an r-outerplanar hypergraph support. That is, the problem is for a given hypergraph to find an r-outerplanar graph on the same vertex set such that each hyperedge induces a connected subgraph. We give an alternative proof that this problem is (strongly uniformly) fixed-parameter tractable with respect to r + m where m is the number of hyperedges in the hypergraph.

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)