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%I #11 Jul 24 2017 12:35:39
%S 16,21,22,55,259,759,32571,179931895322
%N Records of the maxima of the aliquot sequences of the numbers in A290141.
%C a(8) was calculated by D. H. Lehmer.
%e 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.
%t g[n_] := If[n > 0, DivisorSigma[1, n] - n, 0]; f[n_] := NestWhileList[g, n, UnsameQ, All]; rec = {}; a = -1; seq = {}; Do[b = Max[Drop[f[n], 1]];
%t If[b > a, a = b; AppendTo[rec, b]], {n, 2, 275}] ; rec (* after _Robert G. Wilson v_ at A098009 *)
%Y Cf. A008888, A098008, A098009, A098010, A290141.
%K nonn,more
%O 1,1
%A _Amiram Eldar_, Jul 21 2017
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