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 A290141 Numbers n that have a record maximum (> n) in their aliquot sequence. 1
 12, 18, 20, 24, 30, 102, 120, 138 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Maximum term in the aliquot sequence of n is considered only if it is larger than n. The record values are in A290142. LINKS EXAMPLE The aliquot sequence of 30 is: 30, 42, 54, 66, 78, 90, 144, 259, 45, 33, 15, 9, 4, 3, 1. The maximum is 259 which is larger than 30, and larger than the maxima of all the aliquot sequences of the numbers below 30. MATHEMATICA g[n_] := If[n > 0, DivisorSigma[1, n] - n, 0]; f[n_] := NestWhileList[g, n, UnsameQ, All]; seq = {}; a = -1; seq = {}; Do[b = Max[Drop[f[n], 1]];  If[b > a, a = b; AppendTo[seq, n]], {n, 2, 275}]; seq (* after Robert G. Wilson v at A098009 *) CROSSREFS Cf. A098008, A098009, A098010, A290142. Sequence in context: A005101 A124626 A231547 * A087245 A153501 A215012 Adjacent sequences:  A290138 A290139 A290140 * A290142 A290143 A290144 KEYWORD nonn,more AUTHOR Amiram Eldar, Jul 21 2017 STATUS approved

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Last modified March 25 21:57 EDT 2019. Contains 321477 sequences. (Running on oeis4.)