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A321147 Odd exponential abundant numbers: odd numbers n whose sum of exponential divisors A051377(n) > 2n. 0
225450225, 385533225, 481583025, 538472025, 672624225, 705699225, 985646025, 1121915025, 1150227225, 1281998025, 1566972225, 1685513025, 1790559225, 1826280225, 2105433225, 2242496025, 2466612225, 2550755025, 2679615225, 2930852925, 2946861225, 3132081225 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The exponential version of A005231.

The odd subsequence of A129575.

LINKS

Table of n, a(n) for n=1..22.

Eric Weisstein's World of Mathematics, e-Divisor

Eric Weisstein's World of Mathematics, e-Perfect Number

EXAMPLE

225450225 is in the sequence since it is odd and A051377(225450225) = 484323840 > 2 * 225450225.

MATHEMATICA

esigma[n_] := Times @@ (Sum[First[#]^d, {d, Divisors[Last[#]]}] &) /@ FactorInteger[n]; s={}; Do[If[esigma[n]>2n, AppendTo[s, n]], {n, 1, 10^10, 2}]; s

CROSSREFS

Cf. A005231, A051377, A126164, A129485, A129575, A293186.

Sequence in context: A258364 A046327 A206044 * A176364 A283073 A322061

Adjacent sequences:  A321144 A321145 A321146 * A321148 A321149 A321150

KEYWORD

nonn

AUTHOR

Amiram Eldar, Oct 28 2018

STATUS

approved

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Last modified September 22 16:55 EDT 2019. Contains 327311 sequences. (Running on oeis4.)