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%I #10 Jul 24 2017 12:36:14
%S 1,2,3,4,5,6,7,8,9,10,11,15,43,45,67,78,205,207,1109,1116,1117,1155,
%T 1162,1163,1171,1711,1712,1828,1829
%N Record lengths of transient part of the unitary aliquot sequences of the numbers in A290143.
%e The unitary aliquot sequence of 134 is: 134, 70, 74, 40, 14, 10, 8, 1. Its length is 8 and it is longer than the unitary aliquot sequences of all the numbers below 134.
%t usigma[n_] := If[n == 1, 1, Times @@ (1 + Power @@@ FactorInteger[n])];
%t g[n_] := If[n > 0, usigma[n] - n, 0]; f[n_] := NestWhileList[g, n, UnsameQ, All]; a = 0; seq = {}; Do[b = Length[f[n]] - 2; If[b > a, a = b; AppendTo[seq, b]], {n, 10^6}]; seq (* after _Giovanni Resta_ at A034448 & _Robert G. Wilson v_ at A098009 *)
%Y Cf. A098008, A098009, A098010, A127652, A127653, A127654, A127655, A290143.
%K nonn,more
%O 1,2
%A _Amiram Eldar_, Jul 21 2017
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