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On Trees Without Hyperimmune Branches

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Part of the book series: Lecture Notes in Computer Science ((LNCS,volume 13359))

Abstract

The current work includes a result announced in the year 2012 which was unproven until now. The result shows that there is a co-r.e. tree with uncountably many infinite branches such that the nonisolated infinite branches of the constructed tree are all nonrecursive, generalised low, hyperimmune-free and form a perfect tree.

Frank Stephan and Yang Yue have been supported in part by the Singapore Ministry of Education Tier 2 grant AcRF MOE2019-T2-2-121/R146-000-304-112 as well as by the NUS Tier 1 grants AcRF R146-000-337-114 and R252-000-C17-114. Keng Meng Ng is supported by the Singapore Ministry of Education grant RG23/19 at NTU. Liang Yu was supported by NSFC grant No. 12025103.

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Ng, K.M., Stephan, F., Yang, Y., Yu, L. (2022). On Trees Without Hyperimmune Branches. In: Berger, U., Franklin, J.N.Y., Manea, F., Pauly, A. (eds) Revolutions and Revelations in Computability. CiE 2022. Lecture Notes in Computer Science, vol 13359. Springer, Cham. https://doi.org/10.1007/978-3-031-08740-0_20

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  • DOI: https://doi.org/10.1007/978-3-031-08740-0_20

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  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-031-08739-4

  • Online ISBN: 978-3-031-08740-0

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