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%I #15 Jan 13 2022 04:23:43
%S 1,2,3,4,9,16,19,26,29,34,44,51,61,64,69,79,89,106,131,134,139,141,
%T 146,159,166,169,191,194,201,209,211,219,226,236,239,244,251,254,261,
%U 271,274,289,296,299,309,316,321,334,339,341,344,349,359,376,381,386
%N Numbers which are both deficient (A005100) and anti-deficient (A192267).
%H Amiram Eldar, <a href="/A192818/b192818.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1500 from Nathaniel Johnston)
%F A005100 INTERSECTION A192267.
%e 24 is anti-deficient because its anti-divisors are 7, 16 and their sum is 23 < 24. 26 is deficient because its proper divisors are 1, 2, 13 which sum to 16 and 16 < 26.
%t q[n_] := Total[Cases[Range[2, n - 1], _?(Abs[Mod[n, #] - #/2] < 1 &)]] < n && DivisorSigma[1, n] < 2*n; Select[Range[300], q] (* _Amiram Eldar_, Jan 13 2022 after _Michael De Vlieger_ at A066417 *)
%Y Cf. A005100, A066417, A192267.
%K nonn,easy
%O 1,2
%A _Jonathan Vos Post_, Jul 10 2011
%E More terms and inserted a(1)=1 from _Nathaniel Johnston_, Sep 26 2011
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