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Numbers k such that k is equal to the sum of the proper divisors of k that are greater than k^(1/4).
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%I #18 Mar 22 2020 01:59:03

%S 18,1338,1362,1374,1398,1434,1446,1506,1542,1578,1614,1626,1662,1686,

%T 1698,1758,1842,1866,1878,1902,1986,2022,2082,2094,2118,2154,2202,

%U 2238,2274,2298,2334,2382,2406,2454,2514,2526,2586,2598,2634,2658,2694,2742,2766,2778

%N Numbers k such that k is equal to the sum of the proper divisors of k that are greater than k^(1/4).

%C On a suggestion of Manuel Valdivia.

%C Is 8415 the only odd term in this sequence?

%C 8415 is the only odd term < 10^11. - _Donovan Johnson_, Apr 26 2012

%H Amiram Eldar, <a href="/A182286/b182286.txt">Table of n, a(n) for n = 1..10000</a>

%t spdQ[n_]:=Total[Select[Most[Divisors[n]],#>Sqrt[Sqrt[n]]&]]==n; Select[Range[3000],spdQ] (* _Harvey P. Dale_, Aug 17 2012 *)

%Y Cf. A182311.

%K nonn

%O 1,1

%A _Claudio Meller_, Apr 23 2012