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: "positivity problems for low order linear recurrence sequences"
  Abstract: We consider two decision problems for linear recurrence sequences (LRS) over the integers, namely the Positivity Problem (are all terms of a given LRS positive?) and the Ultimate Positivity Problem} (are all but finitely many terms of a given LRS positive?). We show decidability of both problems for LRS of order 5 or less, with complexity in the Counting Hierarchy for Positivity, and in polynomial time for Ultimate Positivity. Moreover, we show by way of hardness that extending the decidability of either problem to LRS of order 6 would entail major breakthroughs in analytic number theory, more precisely in the field of Diophantine approximation of transcendental numbers.

Connected through hyperedge HE-1 (induced by source paper "on the mortality problem from multiplicative matrix equations to linear recurrence sequences and beyond"):
  with members:
    - "on the identity problem for the special linear group and the heisenberg group"
    - "solvability of matrix exponential equations"
    - "on the skolem problem for continuous linear dynamical systems"
    - "on termination of integer linear loops"
    - "tighter undecidability bounds for matrix mortality zero in the corner problems and more"
    - "on the positivity problem for simple linear recurrence sequences"
    - "on the complexity of the orbit problem"

Connected through hyperedge HE-2 (induced by source paper "termination of linear loops over the integers"):
  with members:
    - "multiphase linear ranking functions and their relation to recurrent sets"
    - "effective divergence analysis for linear recurrence sequences"
    - "on multiphase linear ranking functions"
    - "on termination of integer linear loops"
    - "abstract acceleration of general linear loops"
    - "ranking functions for linear constraint loops"

Connected through hyperedge HE-3 (induced by source paper "on reachability problems for low dimensional matrix semigroups"):
  with members:
    - "polynomial invariants for affine programs"
    - "on the identity problem for the special linear group and the heisenberg group"
    - "tighter undecidability bounds for matrix mortality zero in the corner problems and more"

Connected through hyperedge HE-4 (induced by source paper "convex language semantics for nondeterministic probabilistic automata"):
  with members:
    - "the power of convex algebras"
    - "revisiting trace and testing equivalences for nondeterministic and probabilistic processes"
    - "probabilistic bisimulation naturally on distributions"
    - "towards a coalgebraic chomsky hierarchy"
    - "generalizing determinization from automata to coalgebras"

Connected through hyperedge HE-5 (induced by source paper "timed comparisons of semi markov processes"):
  with members:
    - "profinite techniques for probabilistic automata and the markov monoid algorithm"

Connected through hyperedge HE-6 (induced by source paper "the complexity of synchronizing markov decision processes"):
  with members:
    - "improving the upper bound on the length of the shortest reset word"
    - "controlling a population"
    - "synchronizing data words for register automata"
    - "computation tree logic for synchronization properties"
    - "trace refinement in labelled markov decision processes"
    - "synchronizing weighted automata"
    - "probabilistic bisimulation naturally on distributions"
    - "fast synchronization of random automata"

Connected through hyperedge HE-7 (induced by source paper "decision problems on unary probabilistic and quantum automata"):
  with members:
    - "classical and quantum realtime alternating automata"
    - "on the positivity problem for simple linear recurrence sequences"
    - "ultimate positivity is decidable for simple linear recurrence sequences"

Connected through hyperedge HE-8 (induced by source paper "undecidable cases of model checking probabilistic temporal epistemic logic extended abstract"):
  with members:
    - "tighter undecidability bounds for matrix mortality zero in the corner problems and more"

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)