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%I #14 Sep 22 2022 01:40:33
%S 12,20,56,70,88,104,368,464,650,836,1888,1952,4030,5830,8925,11096,
%T 17816,32128,32445,45356,77744,91388,128768,130304,254012,388076,
%U 442365,521728,522752,1848964,2087936,2291936,8378368,8382464,13174976,29465852,35021696,45335936
%N Admirable numbers whose abundance is < 10.
%C Apparently all the abundant numbers with even abundance < 10 are admirable (checked for the first 60 terms). Of the 4 known numbers whose abundance is 10 (A223609), only the first, 40, is admirable. - _Amiram Eldar_, Nov 07 2019
%H Amiram Eldar, <a href="/A109788/b109788.txt">Table of n, a(n) for n = 1..60</a>
%t aQ[n_] := (ab = DivisorSigma[1, n] - 2 n) > 0 && EvenQ[ab] && ab < 10 && ab/2 < n && Divisible[n, ab/2]; Select[Range[10^4], aQ] (* _Amiram Eldar_, Nov 07 2019 *)
%o (PARI) for(n=1,10^9,ap=sigma(n)-2*n;if(ap>0 && ap<10 && (ap%2)==0,d=ap/2;if(d!=n && (n%d)==0, print1(n",")))) - Herman Jamke (hermanjamke(AT)fastmail.fm), Mar 30 2008
%Y Cf. A033880, A111592, A111667.
%K nonn
%O 1,1
%A _Jason Earls_, Aug 14 2005
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Mar 30 2008
%E a(36)-a(38) from _Amiram Eldar_, Nov 07 2019
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