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A045477

Aliquot sequence starting at 840 (reaches 1 at 747th term).

840, 2040, 4440, 9240, 25320, 51000, 117480, 271320, 765480, 1531320, 3721800, 7817640, 15635640, 32899560, 65799480, 139098120, 349027320, 699333000, 1597611000, 3386944680, 9543610200, 20041583280

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OFFSET

0,1

REFERENCES

A. W. P. Guy and R. K. Guy, A record aliquot sequence, pp. 557-559 of Mathematics of Computation 1943-1993 (Vancouver, 1993), Proc. Symp. Appl. Math., Vol. 48, Amer. Math. Soc. 1994.

LINKS

T. D. Noe, Table of n, a(n) for n = 0..748

Christophe CLAVIER, Aliquot Sequences

FORMULA

a(n+1) = A001065(a(n)). - R. J. Mathar, Oct 11 2017

MATHEMATICA

FixedPointList[If[# > 0, DivisorSigma[1, #] - #, 0]&, 840] // Most (* Jean-François Alcover, Mar 28 2020 *)

CROSSREFS

Sequence in context: A169827 A158402 A361421 * A232099 A005952 A260473

Adjacent sequences: A045474 A045475 A045476 * A045478 A045479 A045480

KEYWORD

nonn,fini,full

AUTHOR

N. J. A. Sloane

STATUS

approved