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 A119239 Oddly superabundant numbers: odd n with sigma(n)/n > sigma(k)/k for all odd k < n. 4
 1, 3, 9, 15, 45, 105, 315, 945, 1575, 2835, 3465, 10395, 17325, 31185, 45045, 135135, 225225, 405405, 675675, 2027025, 2297295, 3828825, 6891885, 11486475, 34459425, 43648605, 72747675, 130945815, 218243025, 654729075, 1003917915, 1527701175 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Every oddly colossally abundant number (A110464) is in this sequence. LINKS T. D. Noe, Table of n, a(n) for n = 1..1000 Richard Laatsch, Measuring the abundancy of integers, Mathematics Magazine 59 (2) (1986) 84-92. Walter Nissen, Abundancy : Some Resources MATHEMATICA rec=0; lst={}; Do[abun=DivisorSigma[1, n]/n; If[abun>rec, rec=abun; AppendTo[lst, n]], {n, 1, 10^6, 2}]; lst PROG (PARI) r=0; forstep(n=1, 1e6, 2, t=sigma(n)/n; if(t>r, r=t; print1(n", "))) \\ Charles R Greathouse IV, Nov 27 2013 CROSSREFS Cf. A004394 (superabundant numbers), A005231 (odd abundant numbers), A053624 (highly composite odd numbers). Sequence in context: A065917 A053624 A348198 * A140864 A171929 A188597 Adjacent sequences:  A119236 A119237 A119238 * A119240 A119241 A119242 KEYWORD nonn AUTHOR T. D. Noe, May 09 2006 EXTENSIONS Definition clarified by Jonathan Sondow, Dec 08 2011 STATUS approved

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Last modified December 2 18:11 EST 2021. Contains 349445 sequences. (Running on oeis4.)