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%I #19 Jun 26 2019 09:29:47
%S 2,3,4,5,7,8,9,10,11,13,14,15,16,17,19,20,21,22,23,25,26,27,29,30,31,
%T 32,33,34,35,37,38,39,41,42,43,44,45,46,47,49,50,51,52,53,55,57,58,59,
%U 61,62,63,64,65,66,67,68,69,70,71,73,74,75,76,77,78,79,81,82,83,85,86,87,88,89,91,92,93,94,95,97,98,99,101,102,103,104,105
%N Numbers that are smaller than the sum of their deficient divisors.
%C Contains every deficient number larger than 1 and every primitive abundant number (A071395).
%H Amiram Eldar, <a href="/A254278/b254278.txt">Table of n, a(n) for n = 1..10000</a>
%e a(16) = 20 since 20 is smaller than 22, which is the sum of its deficient divisors.
%t Select[Range@ 105, Function[n, n < Total@ Select[Divisors@ n, DivisorSigma[1, #] < 2 # &]]] (* _Michael De Vlieger_, Jul 16 2016 *)
%o (PARI) isok(n) = n < sumdiv(n, d, d*(sigma(d) < 2*d)); \\ _Michel Marcus_, Jun 26 2019
%Y Cf. A005100, supersequence of A071395 and A198471, A091191.
%K nonn
%O 1,1
%A _Timothy L. Tiffin_, Jul 15 2016
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