|
%I #10 Jun 02 2024 14:40:10
%S 4,2,12,12,10,12,12,8,12,4,12,56,4,12,2,12,120,12,56,12,12,12,56,78,
%T 12,12,180,12,56,12,12,56,12,8,12,12,12,2,12,56,12,56,12,12,12,12,12,
%U 56,2,12,672,12,12,12,56,12,12,8,56,12,12,12,30,12,32,12,56,12,12,12,12,56
%N Abundance of admirable numbers.
%H Amiram Eldar, <a href="/A111667/b111667.txt">Table of n, a(n) for n = 1..10000</a>
%e a(1)=4 because the first admirable number is 12 and sigma(12)-24 = 4.
%t fn[n_]:=DivisorSigma[1,n]-2*n;fn/@Select[Range[1155], MemberQ[Most[Divisors[#]], (DivisorSigma[1, #]-2*#)/2]&] (* _James C. McMahon_, Jun 02 2024 *)
%Y Cf. A033880, A111592.
%K easy,nonn
%O 1,1
%A _Jason Earls_, Aug 14 2005
|
