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: "hitting all maximum cliques with a stable set using lopsided independent transversals"
  Abstract: Rabern recently proved that any graph with **image** contains a stable set meeting all maximum cliques. We strengthen this result, proving that such a stable set exists for any graph with **image**. This is tight, i.e. the inequality in the statement must be strict. The proof relies on finding an independent transversal in a graph partitioned into vertex sets of unequal size. © 2010 Wiley Periodicals, Inc. J Graph Theory 67:300-305, 2011 © 2011 Wiley Periodicals, Inc.

Connected through hyperedge HE-1 (induced by source paper "a short proof that chi can be bounded epsilon away from delta 1 towards omega"):
  with members:
    - "a local strengthening of reed s omega delta chi conjecture for quasi line graphs"

Connected through hyperedge HE-2 (induced by source paper "a set and collection lemma"):
  with members:
    - "a note on hitting maximum and maximal cliques with a stable set"

Connected through hyperedge HE-3 (induced by source paper "a note on hitting maximum and maximal cliques with a stable set"):
  with members:
    - "a local strengthening of reed s omega delta chi conjecture for quasi line 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)