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A074907
Aliquot sequence starting at 570.
3
570, 870, 1290, 1878, 1890, 3870, 6426, 10854, 13830, 19434, 20886, 21606, 25098, 26742, 26754, 40446, 63234, 77406, 110754, 171486, 253458, 295740, 647748, 1077612, 1467588, 1956812, 2109796, 1889486, 953914, 668966, 353578, 176792
OFFSET
0,1
REFERENCES
R. K. Guy, Unsolved Problems in Number Theory, B6.
LINKS
Christophe CLAVIER, Aliquot Sequences
FORMULA
a(n+1) = A001065(a(n)). - R. J. Mathar, Oct 11 2017
EXAMPLE
a(0) = 570, a(1) = sigma(570) - 570 = 870.
MATHEMATICA
FixedPointList[If[# > 0, DivisorSigma[1, #] - #, 0]&, 570] // Most (* Jean-François Alcover, Mar 28 2020 *)
CROSSREFS
Sequence in context: A252473 A252466 A097035 * A231140 A268203 A268248
KEYWORD
nonn,fini,full
AUTHOR
Robert A. Stump (bee_ess107(AT)msn.com), Sep 30 2002
STATUS
approved