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 A077006 Numbers n such that sigma(n)/n >= sigma(m)/m for all m <= n. 3
 1, 2, 4, 6, 12, 24, 36, 48, 60, 120, 180, 240, 360, 720, 840, 1260, 1680, 2520, 5040, 10080, 15120, 25200, 27720, 55440, 110880, 166320, 277200, 332640, 360360, 554400, 665280, 720720, 1441440, 2162160, 3603600, 4324320, 7207200, 8648640, 10810800, 21621600 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE 360360 is included in this sequence (but not in A004394) because its abundancy (sigma(n)/n = 48/11) is the same as that of the previous record holder (namely 332640). - Gerard P. Michon, May 20 2009 MATHEMATICA abund[n_] := abund[n] = DivisorSigma[1, n]/n; ok[n_] := (r = True; m = 1; While[m <= n, If[abund[n] < abund[m], r = False; Break[]]; m++]; r); n = 1; A077006 = {}; While[n < 10^6, If[ok[n], Print[n]; AppendTo[ A077006, n]]; n++]; A077006 (* Jean-François Alcover, Dec 12 2011 *) CROSSREFS Almost same as A004394. Sequence in context: A094348 A242298 A002182 * A166981 A004394 A189686 Adjacent sequences:  A077003 A077004 A077005 * A077007 A077008 A077009 KEYWORD nice,nonn AUTHOR Mike Speciner, Oct 15 2003 EXTENSIONS a(31)-a(40) from Jon E. Schoenfield, Mar 31 2018 STATUS approved

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Last modified July 21 00:49 EDT 2019. Contains 325189 sequences. (Running on oeis4.)