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%I #19 Sep 15 2019 07:56:24
%S 2,3,4,21,26,27,33,35,38,46,58,62,74,475,605,1083,1719,2007,2151,2169,
%T 2259,2313,2421,2431,2439,2493,2529,2547,2637,2737,2763,2799,2979,
%U 3123,3303,3357,3367,3451,3619,3681,3698,4255,4465,4625,5035,5125,5185,5695,6205
%N Floor(sqrt(n))-perfect numbers.
%C See definition in comment to A175522.
%C The even terms begin: 2, 4, 26, 38, 46, 58, 62, 74, 3698, 34226, 34726, ... - _Michel Marcus_, Feb 08 2016
%H Amiram Eldar, <a href="/A176234/b176234.txt">Table of n, a(n) for n = 1..10000</a>
%e floor(sqrt(35))=5; floor(sqrt(1))+floor(sqrt(5))+floor(sqrt(7))=5. Therefore, 35 is in the sequence.
%t f[n_] := Sum[Floor[Sqrt[Divisors[n][[i]]]], {i, 1, Length[Divisors[n]] - 1}]; Select[Range[3000], f[#] == Floor[Sqrt[#]] &]
%o (PARI) isok(n) = sumdiv(n, d, (d<n)* sqrtint(d)) == sqrtint(n); \\ _Michel Marcus_, Feb 08 2016
%Y Cf. A175522, A000396, A175807.
%K nonn
%O 1,1
%A _Vladimir Shevelev_, Dec 07 2010
%E More terms from _Michel Marcus_, Feb 08 2016
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