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: "on the structure of pan even hole free graphs"
  Abstract: A hole is a chordless cycle with at least four vertices. A pan is a graph which consists of a hole and a single vertex with precisely one neighbor on the hole. An even hole is a hole with an even number of vertices. We prove that a (pan, even hole)-free graph can be decomposed by clique cutsets into essentially unit circular-arc graphs. This structure theorem is the basis of our $O(nm)$-time certifying algorithm for recognizing (pan, even hole)-free graphs and for our $O(n^{2.5}+nm)$-time algorithm to optimally color them. Using this structure theorem, we show that the tree-width of a (pan, even hole)-free graph is at most 1.5 times the clique number minus 1.

Connected through hyperedge HE-1 (induced by source paper "theta triangle free and even hole k 4 free graphs part 2 bounds on treewidth"):
  with members:
    - "polynomial time algorithm for maximum weight independent set on p_6 free graphs"
    - "colouring diamond free graphs"
    - "maximum weight independent sets for p_7 triangle free graphs in polynomial time"
    - "clique width of graph classes defined by two forbidden induced subgraphs"

Connected through hyperedge HE-2 (induced by source paper "three in a tree in near linear time"):
  with members:
    - "graph pattern detection hardness for all induced patterns and faster non induced cycles"
    - "a faster algorithm to recognize even hole free graphs"
    - "powers of tensors and fast matrix multiplication"
    - "detecting an induced net subdivision"
    - "large induced subgraphs via triangulations and cmso"
    - "induced disjoint paths in claw free graphs"
    - "detecting 2 joins faster"
    - "the k in a path problem for claw free graphs"

Connected through hyperedge HE-3 (induced by source paper "theta triangle free and even hole k_4 free graphs part 1 layered wheels"):
  with members:
    - "improved bounds for the excluded grid theorem"
    - "structure and algorithms for cap even hole free graphs"
    - "on rank width of even hole free graphs"
    - "the k in a path problem for claw free graphs"

Connected through hyperedge HE-4 (induced by source paper "square free graphs with no six vertex induced path"):
  with members:
    - "bounding the clique width of h free chordal graphs"

Connected through hyperedge HE-5 (induced by source paper "on h topological intersection graphs"):
  with members:
    - "a note on the complexity of feedback vertex set parameterized by mim width"
    - "on the number of minimal separators in graphs"
    - "extending partial representations of subclasses of chordal graphs"
    - "isomorphism of graph classes related to the circular ones property"
    - "the maximum clique problem in multiple interval graphs"

Connected through hyperedge HE-6 (induced by source paper "structure and algorithms for cap even hole free graphs"):
  with members:
    - "the behavior of clique width under graph operations and graph transformations"
    - "vertex elimination orderings for hereditary graph classes"
    - "a faster algorithm to recognize even hole free graphs"

Connected through hyperedge HE-7 (induced by source paper "a note on coloring even hole cap free graphs"):
  with members:
    - "a faster algorithm to recognize even hole free 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)