We present a variety of numerical data related to the growth of terms in aliquot sequences, iterations of the function s(n) = σ(n) − n. First, we compute the geometric mean of the ratio s k (n)/s k−1 (n) of kth iterates for n ≤ 2 37 and k = 1, . . . , 10. Second, we extend the computation of numbers not in the range of s(n) (called untouchable) by Pollack and Pomerance [2016] to the bound of 2 40 and use these data to compute the geometric mean of the ratio of consecutive terms limited to terms in the range of s(n). Third, we give an algorithm to compute k-untouchable numbers (k − 1st iterates of s(n) but not kth iterates) along with some numerical data. Finally, inspired by earlier work of Devitt [1976], we estimate the growth rate of terms in aliquot sequences using a Markov chain model based on data extracted from thousands of sequences.
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