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%I #4 Jan 06 2020 20:34:11
%S 3,10,21,63,104,152,170,358,567,651,3826,4664,5583,5943,39248,943228,
%T 1906503,9166540,35702868,701792828,825415941,2275142000,5805372939
%N Numbers that equal to the sum of their iterated absolute alternating sum-of-divisors function (A206369).
%e 10 is a term since the iterations of A206369 with a starting value of 10 give A206369(10) = 4, A206369(4) = 3, A206369(3) = 2, and A206369(2) = 1, whose sum is 4 + 3 + 2 + 1 = 10.
%t f[p_, e_] := Sum[(-1)^(e - k)*p^k, {k, 0, e}]; s[1] = 1; s[n_] := s[n] = Times @@ (f @@@ FactorInteger[n]); Select[Range[1000], Plus @@ FixedPointList[s, #] == 2 # + 1 &]
%Y Cf. A082897, A206369, A330786 (number of iterations).
%K nonn,more
%O 1,1
%A _Amiram Eldar_, Jan 06 2020
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