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%I #9 Apr 16 2024 14:03:39
%S 12110,1596770,1629364,4265590,4442690,6015310,7122290,7142030,
%T 8438990,8837570,8877890,9667910,9989770,10106810,10867570,11130910,
%U 11306470,11511290,12008710,12096490,12623170,12915770,13281170,13390510,13852090,14144690,14583590,14817670
%N Weird numbers whose abundance is also a weird number.
%C Terms k of A006037 such that A033880(k) is also a term of A006037.
%H Amiram Eldar, <a href="/A371952/b371952.txt">Table of n, a(n) for n = 1..10000</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Weird_number">Weird number</a>.
%e 12110 is a term because it is a weird number, and A033880(12110) = sigma(12110) - 2*12110 = 836 is also a weird number.
%t With[{weirds = Import["https://oeis.org/a006037/b006037.txt", "Table"][[;; , 2]]}, Select[weirds, (ab = DivisorSigma[1, #] - 2*#) <= Last[weirds] && MemberQ[weirds, ab] &]]
%Y Subsequence of A006037 and A371920.
%Y A371953 is a subsequence.
%Y Cf. A000203 (sigma), A033880 (abundance), A371950.
%K nonn
%O 1,1
%A _Amiram Eldar_, Apr 14 2024