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A094889 Odd nonunitary abundant numbers. 3
33075, 99225, 165375, 231525, 259875, 297675, 363825, 429975, 467775, 496125, 552825, 562275, 571725, 606375, 628425, 675675, 694575, 716625, 760725, 779625, 798525, 826875, 848925, 883575, 893025, 921375, 937125, 959175, 1003275 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

J. A. Sellers, A Note On Infinitely Many Odd Nonunitary Abundant Numbers

MATHEMATICA

f[p_, e_] := (p^(e + 1) - 1)/(p - 1); nuabQ[n_] := Times @@ (f @@@ FactorInteger[n]) - Times @@ (1 + Power @@@ FactorInteger[n]) > n; Select[Range[3, 10^6, 2], nuabQ] (* Amiram Eldar, May 12 2019 *)

PROG

(PARI) { usigma(n)=local(s=1, fac, i); fac=factor(n); for(i=1, matsize(fac)[1], s=s*(1+fac[i, 1]^fac[i, 2])); return(s); } nusigma(n)=sigma(n)-usigma(n); forstep(n=1, 2^24, 2, if(nusigma(n)>n, print1(n", ")))

CROSSREFS

Cf. A064597.

Sequence in context: A118278 A118280 A062682 * A332200 A031660 A252291

Adjacent sequences:  A094886 A094887 A094888 * A094890 A094891 A094892

KEYWORD

nonn

AUTHOR

Lekraj Beedassy, Jun 16 2004

EXTENSIONS

Corrected and extended by Jason Earls, Jun 18 2004

STATUS

approved

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Last modified August 7 11:08 EDT 2020. Contains 336275 sequences. (Running on oeis4.)