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A034091 Records for sum of proper divisors function. 8
0, 1, 3, 6, 7, 8, 16, 21, 22, 36, 42, 55, 76, 108, 123, 140, 144, 156, 172, 240, 259, 312, 366, 384, 504, 531, 568, 656, 810, 924, 1032, 1056, 1140, 1260, 1356, 1698, 2040, 2088, 2216, 2520, 2644, 3108, 3474, 3480, 4272, 4572, 4844, 5280, 5304, 5412, 6840 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

T. D. Noe and Donovan Johnson, Table of n, a(n) for n = 1..1000 (first 372 terms from T. D. Noe)

MATHEMATICA

With[{list1=DeleteDuplicates[Array[DivisorSigma[1, #]-#&, 3000, 0]]}, list2 = {}; Table[If[list1[[n]]>Max[list2], AppendTo[list2, list1[[n]]]], {n, Length[ list1]}]; list2] (* Harvey P. Dale, Dec 30 2011 *)

t = {0}; n = 1; mx = 0; While[Length[t] < 100, n++; s = DivisorSigma[1, n] - n; If[s > mx, mx = s; AppendTo[t, mx]]]; t (* T. D. Noe, Feb 23 2012 *)

PROG

(PARI) r=0; for(n=1, 1e9, t=sigma(n)-n; if(t>r, r=t; print1(t", "))) \\ Charles R Greathouse IV, Feb 09 2017

CROSSREFS

Cf. A001065, A034090.

Sequence in context: A189211 A301287 A310133 * A278812 A111717 A181911

Adjacent sequences:  A034088 A034089 A034090 * A034092 A034093 A034094

KEYWORD

nonn,nice

AUTHOR

N. J. A. Sloane, J. Lowell

EXTENSIONS

More terms from Erich Friedman.

STATUS

approved

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Last modified February 27 15:59 EST 2020. Contains 332307 sequences. (Running on oeis4.)