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A348275 Odd noninfinitary abundant numbers: the odd terms of A348274. 4
99225, 1091475, 1289925, 1334025, 1576575, 1686825, 1715175, 1863225, 1885275, 2027025, 2061675, 2282175, 2304225, 2395575, 2401245, 2436525, 2480625, 2650725, 2723175, 2789325, 2877525, 2962575, 3031875, 3075975, 3132675, 3185325, 3186225, 3296475, 3353805, 3501225 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The number of terms below 10^k, for k = 5, 6, ..., are 1, 113, 630, 7771, 73685, ... Apparently this sequence has an asymptotic density 0.000007...
LINKS
EXAMPLE
99225 is a term since A348271(99225) = 107207 > 99225.
MATHEMATICA
f[p_, e_] := Module[{b = IntegerDigits[e, 2], m}, m = Length[b]; Product[If[b[[j]] > 0, 1 + p^(2^(m - j)), 1], {j, 1, m}]]; isigma[1] = 1; isigma[n_] := Times @@ f @@@ FactorInteger[n]; s[n_] := DivisorSigma[1, n] - isigma[n]; Select[Range[1, 2*10^6, 2], s[#] > # &]
CROSSREFS
Cf. A348271.
Subsequence of A005231 and A348274.
Similar sequences: A094889, A127666, A129485, A293186, A321147.
Sequence in context: A255753 A254842 A339936 * A138732 A108224 A268417
KEYWORD
nonn
AUTHOR
Amiram Eldar, Oct 09 2021
STATUS
approved

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Last modified June 19 13:40 EDT 2024. Contains 373503 sequences. (Running on oeis4.)