This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A192818 #15 Jan 13 2022 04:23:43 %S A192818 1,2,3,4,9,16,19,26,29,34,44,51,61,64,69,79,89,106,131,134,139,141, %T A192818 146,159,166,169,191,194,201,209,211,219,226,236,239,244,251,254,261, %U A192818 271,274,289,296,299,309,316,321,334,339,341,344,349,359,376,381,386 %N A192818 Numbers which are both deficient (A005100) and anti-deficient (A192267). %H A192818 Amiram Eldar, <a href="/A192818/b192818.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1500 from Nathaniel Johnston) %F A192818 A005100 INTERSECTION A192267. %e A192818 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 A192818 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 A192818 Cf. A005100, A066417, A192267. %K A192818 nonn,easy %O A192818 1,2 %A A192818 _Jonathan Vos Post_, Jul 10 2011 %E A192818 More terms and inserted a(1)=1 from _Nathaniel Johnston_, Sep 26 2011