A074907 - OEIS

A074907

Aliquot sequence starting at 570.

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

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,1

REFERENCES

R. K. Guy, Unsolved Problems in Number Theory, B6.

LINKS

R. J. Mathar, Table of n, a(n) for n = 0..173

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

Cf. A008888, A008889.

Sequence in context: A252473 A252466 A097035 * A231140 A268203 A268248

Adjacent sequences: A074904 A074905 A074906 * A074908 A074909 A074910

KEYWORD

nonn,fini,full

AUTHOR

Robert A. Stump (bee_ess107(AT)msn.com), Sep 30 2002

STATUS

approved