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 A070061 Least number of fecundity n (A070562). 2
 0, 5, 25, 19, 23, 18, 9, 7, 4, 2, 1, 282, 1529, 1586, 1397, 898, 658, 538, 477, 529, 736, 586, 397, 366, 294, 246, 243, 187, 3237326, 3677393, 3586673, 3553787, 3515987, 22572473, 518376965, 516675965, 516963965, 41883474553, 41881554553, 41863638649, 35632297938395 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS a(41) > 2.75*10^14. - Giovanni Resta, Jun 04 2013 REFERENCES P. Tougne, Jeux Mathematiques column, Pour La Science (French edition of "Scientific American"), Vol. 82, Aug. 1984, Prob. 6, pp. 101, 104. LINKS EXAMPLE a(9)=2 since we have the 9-step chain 2 -> 4 -> 8 -> 16 -> 22 -> 26 -> 38 -> 62 -> 74 -> 102. MATHEMATICA f[n_] := Length@ FixedPointList[ # + Times @@ IntegerDigits@# &, n] - 2; t = Table[0, {50}]; k = 1; While[k < 2300000001, a = f@k; If[ t[[a + 1]] == 0, t[[a + 1]] = k; Print[{k, a}]]; k++ ]; t (* Robert G. Wilson v, Jun 27 2010 *) CROSSREFS Cf. A070562, A070257, A003001. Sequence in context: A070384 A070377 A070383 * A070376 A036139 A070382 Adjacent sequences:  A070058 A070059 A070060 * A070062 A070063 A070064 KEYWORD base,hard,nonn AUTHOR Lekraj Beedassy, May 06 2002 EXTENSIONS Corrected and extended by Jason Earls, May 26 2002 a(34) - a(36) from Robert G. Wilson v, Jun 27 2010 a(37)-a(40) from Giovanni Resta, Jun 04 2013 STATUS approved

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Last modified June 4 05:19 EDT 2020. Contains 334815 sequences. (Running on oeis4.)