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 A044050 a(n) = "length" of the aliquot sequence for n. 7
 1, 2, 2, 3, 2, 1, 2, 3, 4, 4, 2, 7, 2, 5, 5, 6, 2, 4, 2, 7, 3, 6, 2, 5, 1, 7, 3, 1, 2, 15, 2, 3, 6, 8, 3, 4, 2, 7, 3, 4, 2, 14, 2, 5, 7, 8, 2, 6, 4, 3, 4, 9, 2, 13, 3, 5, 3, 4, 2, 11, 2, 9, 3, 4, 3, 12, 2, 5, 4, 6, 2, 9, 2, 5, 5, 5, 3, 11, 2, 7, 5, 6, 2, 6, 3, 9, 7, 7, 2, 10, 4, 6, 4, 4, 2, 9, 2, 3, 4, 5, 2, 18 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The aliquot sequence for n is the trajectory of n under repeated application of the map A001065 = x -> sigma(x) - x. The trajectory will either have a transient part followed by a cyclic part, or have an infinite transient part and never cycle. Sequence gives (length of transient part of trajectory) + (length of cycle if the trajectory did not reach 0). In other words, here we consider that the trajectory ends if we reach 1. Given that A001065(n) is the sum of the divisors of n which are less than n, we have that the aliquot length A(n) = r-1 where r is the smallest integer such that A001065^r(n) = A001065^s(n) for some s

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Last modified January 26 13:09 EST 2022. Contains 350598 sequences. (Running on oeis4.)