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A003416 Sociable numbers: smallest member of each cycle. 9
12496, 14316, 1264460, 2115324, 2784580, 4938136, 7169104, 18048976, 18656380, 28158165, 46722700, 81128632, 174277820, 209524210, 330003580, 498215416, 805984760, 1095447416, 1236402232, 1276254780, 1799281330 (list; graph; refs; listen; history; text; internal format)



Numbers belonging to aliquot cycles of length greater than 2.

The lengths of the corresponding aliquot cycles are given by A052470. - Michel Marcus, Nov 15 2013


R. K. Guy, Unsolved Problems Number Theory, B7.

P. Poulet, Parfaits, amiables et extensions, Editions Stevens, Bruxelles, 1918.

D. Wells, The Penguin Dictionary of Curious and Interesting Numbers, pp. 174 Penguin Books 1987.


Jeppe Stig Nielsen, Table of n, a(n) for n = 1..53

V. E. Hoggart, Jr., Letters to N. J. A. Sloane, 1974-1975

INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 112

D. Moews, Perfect, amicable and sociable numbers

D. Moews, Sociable numbers

J. O. M. Pedersen, Tables of Aliquot Cycles [Broken link]

J. O. M. Pedersen, Tables of Aliquot Cycles [Via Internet Archive Wayback-Machine]

J. O. M. Pedersen, Tables of Aliquot Cycles [Cached copy, pdf file only]

Eric Weisstein's World of Mathematics, Sociable Numbers.


Cf. A072890, A072891.

Sequence in context: A232104 A122726 A072891 * A178278 A335989 A220026

Adjacent sequences:  A003413 A003414 A003415 * A003417 A003418 A003419




N. J. A. Sloane


Incorrect g.f. deleted by N. J. A. Sloane, Sep 20 2008



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Last modified April 19 07:53 EDT 2021. Contains 343109 sequences. (Running on oeis4.)