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: "ergodic mean payoff games for the analysis of attacks in crypto currencies"
  Abstract: Crypto-currencies are digital assets designed to work as a medium of exchange, e.g., Bitcoin, but they are susceptible to attacks (dishonest behavior of participants). A framework for the analysis of attacks in crypto-currencies requires (a) modeling of game-theoretic aspects to analyze incentives for deviation from honest behavior; (b) concurrent interactions between participants; and (c) analysis of long-term monetary gains. Traditional game-theoretic approaches for the analysis of security protocols consider either qualitative temporal properties such as safety and termination, or the very special class of one-shot (stateless) games. However, to analyze general attacks on protocols for crypto-currencies, both stateful analysis and quantitative objectives are necessary. In this work our main contributions are as follows: (a) we show how a class of concurrent mean-payoff games, namely ergodic games, can model various attacks that arise naturally in crypto-currencies; (b) we present the first practical implementation of algorithms for ergodic games that scales to model realistic problems for crypto-currencies; and (c) we present experimental results showing that our framework can handle games with thousands of states and millions of transitions.

Connected through hyperedge HE-1 (induced by source paper "a survey on applications of game theory in blockchain"):
  with members:
    - "a survey on consensus mechanisms and mining strategy management in blockchain networks"
    - "security services using blockchains a state of the art survey"
    - "blockchain governance game"
    - "exchange of renewable energy among prosumers using blockchain with dynamic pricing"
    - "game of coins"
    - "delayed blockchain protocols"
    - "reward sharing schemes for stake pools"
    - "a survey on the security of blockchain systems"

Connected through hyperedge HE-2 (induced by source paper "cost analysis of nondeterministic probabilistic programs"):
  with members:
    - "computational approaches for stochastic shortest path on succinct mdps"
    - "effective divergence analysis for linear recurrence sequences"
    - "automated recurrence analysis for almost linear expected runtime bounds"
    - "bounded expectations resource analysis for probabilistic programs"
    - "termination of nondeterministic recursive probabilistic programs"
    - "a new proof rule for almost sure termination"
    - "lexicographic ranking supermartingales an efficient approach to termination of probabilistic programs"
    - "non polynomial worst case analysis of recursive programs"

Connected through hyperedge HE-3 (induced by source paper "probabilistic smart contracts secure randomness on the blockchain"):
  with members:
    - "quantitative analysis of smart contracts"
    - "computational approaches for stochastic shortest path on succinct mdps"
    - "when can a distributed ledger replace a trusted third party"
    - "securify practical security analysis of smart contracts"
    - "cantor meets scott semantic foundations for probabilistic networks"
    - "termination analysis of probabilistic programs through positivstellensatz s"
    - "reasoning about recursive probabilistic programs"

Connected through hyperedge HE-4 (induced by source paper "the impatient may use limited optimism to minimize regret"):
  with members:
    - "on delay and regret determinization of max plus automata"
    - "admissibility in quantitative graph games"
    - "reactive synthesis without regret"
    - "non zero sum games for reactive synthesis"
    - "minimizing regret in discounted sum games"
    - "iterated regret minimization in game graphs"

Connected through hyperedge HE-5 (induced by source paper "quantitative analysis of smart contracts"):
  with members:
    - "bitcoin s security model revisited"
    - "optimal selfish mining strategies in bitcoin"
    - "qualitative analysis of concurrent mean payoff games"
    - "counterexample guided planning"
    - "better quality in synthesis through quantitative objectives"

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.CR(Cryptography and Security)