Abstract
Given a permutation ω of {1, …, n}, let R(ω) be the root degree of ω, i.e. the smallest (prime) integer r such that there is a permutation σ with ω = σ r. We show that, for ω chosen uniformly at random, R(ω) = (lnlnn − 3lnlnln n + O p(1))−1 lnn, and find the limiting distribution of the remainder term.
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Research supported in part by NSF grants CCR-0225610, DMS-0505550 and ARO grant W911NF-06-1-0076.
Research supported by NSF grant DMS-0406024.
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Bollobás, B., Pittel, B. The distribution of the root degree of a random permutation. Combinatorica 29, 131–151 (2009). https://doi.org/10.1007/s00493-009-2343-3
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DOI: https://doi.org/10.1007/s00493-009-2343-3