Abstract
The problem of whether a certain set of number-theoretic functions – defined via tetration (i.e. iterated exponentiation) – is well-ordered by the majorisation relation, was posed by Skolem in 1956. We prove here that indeed it is a computable well-order, and give a lower bound τ 0 on its ordinal.
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Barra, M., Gerhardy, P. (2009). Skolem + Tetration Is Well-Ordered. In: Ambos-Spies, K., Löwe, B., Merkle, W. (eds) Mathematical Theory and Computational Practice. CiE 2009. Lecture Notes in Computer Science, vol 5635. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-03073-4_2
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DOI: https://doi.org/10.1007/978-3-642-03073-4_2
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-03072-7
Online ISBN: 978-3-642-03073-4
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