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 A097030 Numbers in the cycle-attractors of length=14 if the function f(x)=A063919(x) is iterated; f(x) is the sum of unitary proper divisors. 21
 2418, 2958, 3522, 3534, 3582, 3774, 3906, 3954, 3966, 3978, 4146, 4158, 4434, 4446, 24180, 29580, 35220, 35238, 35340, 35820, 37740, 38682, 39060, 39540, 39660, 39780, 41460, 41580, 44340, 44460, 45402, 49878, 65190, 65322, 74430, 74610, 74790, 98106, 101478, 117258, 117270, 117450 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This sequence collects 14-cycle-attractor elements for iteration of sum-proper-unitary-divisors. A002827 provides 1-cycle terms = unitary perfect numbers. A063991 gives 2-cycle elements = unitary amicable numbers. A097024 collects true 5-cycle elements, i.e., terms in end-cycle of length 5 when A063919(x) function is iterated. Concerning 3-cycle elements, only {30,42,54} were encountered. LINKS J. O. M. Pedersen, Known Unitary Sociable Numbers of order different from four [Via Internet Archive Wayback-Machine] J. O. M. Pedersen, Order 14 cycles, 2007. EXAMPLE These 42 numbers are in 3 different 14-cycles. The first is: [2418, 2958, 3522, 3534, 4146, 4158, 3906, 3774, 4434, 4446, 3954, 3966, 3978, 3582]. [edited by Michel Marcus, Sep 29 2018] CROSSREFS Cf. A063919, A002827, A063991, A097024. Sequence in context: A159346 A256835 A237940 * A204367 A131759 A254901 Adjacent sequences:  A097027 A097028 A097029 * A097031 A097032 A097033 KEYWORD nonn AUTHOR Labos Elemer, Aug 30 2004 EXTENSIONS More terms from Michel Marcus, Sep 29 2018 STATUS approved

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Last modified December 12 20:12 EST 2019. Contains 329961 sequences. (Running on oeis4.)