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: "blocksci design and applications of a blockchain analysis platform"
  Abstract: Analysis of blockchain data is useful for both scientific research and commercial applications. We present BlockSci, an open-source software platform for blockchain analysis. BlockSci is versatile in its support for different blockchains and analysis tasks. It incorporates an in-memory, analytical (rather than transactional) database, making it several hundred times faster than existing tools. We describe BlockSci's design and present four analyses that illustrate its capabilities. #R##N#This is a working paper that accompanies the first public release of BlockSci, available at this https URL We seek input from the community to further develop the software and explore other potential applications.

Connected through hyperedge HE-1 (induced by source paper "xblock eth extracting and exploring blockchain data from ethereum"):
  with members:
    - "blockchain for internet of things a survey"
    - "measurement and analysis of the bitcoin networks a view from mining pools"
    - "decentralization in bitcoin and ethereum networks"
    - "contractfuzzer fuzzing smart contracts for vulnerability detection"
    - "an adaptive gas cost mechanism for ethereum to defend against under priced dos attacks"
    - "dissecting ponzi schemes on ethereum identification analysis and impact"
    - "blockbench a framework for analyzing private blockchains"
    - "online human bot interactions detection estimation and characterization"

Connected through hyperedge HE-2 (induced by source paper "safeguarding the evidential value of forensic cryptocurrency investigations"):
  with members:
    - "ransomware payments in the bitcoin ecosystem"
    - "an empirical analysis of anonymity in zcash"
    - "an empirical analysis of linkability in the monero blockchain"
    - "counterfactual explanations without opening the black box automated decisions and the gdpr"
    - "when the cookie meets the blockchain privacy risks of web payments via cryptocurrencies"
    - "the unreasonable effectiveness of address clustering"

Connected through hyperedge HE-3 (induced by source paper "investigating mmm ponzi scheme on bitcoin"):
  with members:
    - "finding the greedy prodigal and suicidal contracts at scale"
    - "data mining for detecting bitcoin ponzi schemes"
    - "deanonymizing tor hidden service users through bitcoin transactions analysis"
    - "blocktag design and applications of a tagging system for blockchain analysis"
    - "when a small leak sinks a great ship deanonymizing tor hidden service users through bitcoin transactions analysis"
    - "dissecting ponzi schemes on ethereum identification analysis and impact"

Connected through hyperedge HE-4 (induced by source paper "spams meet cryptocurrencies sextortion in the bitcoin ecosystem"):
  with members:
    - "ransomware payments in the bitcoin ecosystem"
    - "economic analysis of ransomware"
    - "the unreasonable effectiveness of address clustering"
    - "learning to filter spam e mail a comparison of a naive bayesian and a memory based approach"

Connected through hyperedge HE-5 (induced by source paper "techniques and applications for crawling ingesting and analyzing blockchain data"):
  with members:
    - "data mining for detecting bitcoin ponzi schemes"
    - "blockbench a framework for analyzing private blockchains"
    - "bitcoin transaction graph analysis"

Connected through hyperedge HE-6 (induced by source paper "selecting reliable blockchain peers via hybrid blockchain reliability prediction"):
  with members:
    - "blockbench a framework for analyzing private blockchains"
    - "empirical analysis of predictive algorithms for collaborative filtering"

Connected through hyperedge HE-7 (induced by source paper "characterizing bitcoin donations to open source software on github"):
  with members:
    - "blocktag design and applications of a tagging system for blockchain analysis"

Connected through hyperedge HE-8 (induced by source paper "blocktag design and applications of a tagging system for blockchain analysis"):
  with members:
    - "data mining for detecting bitcoin ponzi schemes"
    - "the rise of social bots"
    - "bitcoin transaction graph analysis"
    - "a survey on truth discovery"
    - "deanonymisation of clients in bitcoin p2p network"
    - "bitcoin over tor isn t a good idea"
    - "content and popularity analysis of tor hidden services"

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)