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 A098009 Numbers n such that transient part of the aliquot sequence for n is finite and sets a new record. 10
 1, 2, 4, 9, 12, 30, 102, 138 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS In order to extend this there is the problem that there are small numbers (276, 552, etc.) for which it is not presently known if they cycle. I propose that we assume these do not cycle, but mark the records beyond where this becomes an issue as conjectural only. REFERENCES See references and links in A098007, A098008. LINKS EXAMPLE 138 has a transient of length 177 (see Guy's book). MATHEMATICA g[n_] := If[n > 0, DivisorSigma[1, n] - n, 0]; f[n_] := NestWhileList[g, n, UnsameQ, All]; a = -1; Do[b = Length[ f[n]] - 1; If[b > a, a = b; Print[n]], {n, 275}] (* Robert G. Wilson v, Sep 10 2004 *) CROSSREFS Records in A098008. Cf. A098010. Sequence in context: A176472 A139557 A103690 * A129376 A266582 A227759 Adjacent sequences:  A098006 A098007 A098008 * A098010 A098011 A098012 KEYWORD nonn,more AUTHOR N. J. A. Sloane, Sep 10 2004 EXTENSIONS 102 and 138 from Robert G. Wilson v, Sep 10 2004 STATUS approved

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Last modified October 17 22:44 EDT 2019. Contains 328134 sequences. (Running on oeis4.)