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Deficiency of n-th deficient number: 2k - sigma(k) for k such that this is > 0.
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%I #14 Oct 05 2019 11:31:21

%S 1,1,2,1,4,6,1,5,2,10,12,4,6,1,16,18,10,8,22,19,10,14,28,30,1,18,14,

%T 22,36,16,22,40,42,4,12,20,46,41,7,30,6,52,38,34,26,58,60,28,22,1,46,

%U 66,10,42,70,72,34,26,12,58,78,41,38,82,62,40,54,88,70,16,58,44,70,96,25

%N Deficiency of n-th deficient number: 2k - sigma(k) for k such that this is > 0.

%H Amiram Eldar, <a href="/A033884/b033884.txt">Table of n, a(n) for n = 1..10000</a>

%p with(numtheory): for n from 1 to 500 do if 2*n - sigma(n)> 0 then printf(`%d,`,2*n - sigma(n)) fi: od:

%t Select[(2 # - DivisorSigma[1, #]) & /@ Range[100], # > 0 &] (* _Amiram Eldar_, Aug 03 2019 *)

%Y Cf. A000203, A005100, A033879.

%K nonn

%O 1,3

%A _N. J. A. Sloane_

%E More terms from _James A. Sellers_, Feb 19 2001