%I #17 May 04 2019 21:50:36
%S 7,167,507,543,3433,6707,9615,15690,87667,1023971,2054435,5871045,
%T 9150387,14146891,63538839,169623015
%N Super anti-perfect numbers.
%C Like A019279 but using anti-divisors. sigma*^2(n)=sigma*(sigma*(n))=2n, where sigma*(n) is the sum of the anti-divisors of n.
%p for n from 1 do
%p if A066417(A066417(n)) = 2*n then
%p print(n);
%p end if;
%p end do: # _R. J. Mathar_, Oct 02 2011
%Y Cf. A019279, A066417.
%K nonn,more
%O 1,1
%A _Paolo P. Lava_, Jun 28 2011
%E a(9)-a(16) from _Donovan Johnson_, Sep 22 2011
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