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%I #22 Mar 04 2018 03:11:03
%S 1,3,3,9,3,6,3,9,6,6,3,18,3,6,9,9,3,18,3,18,9,6,3,9,6,6,6,18,3,6,3,9,
%T 9,6,9,36,3,6,9,9,3,6,3,18,18,6,3,18,6,18,9,18,3,9,9,9,9,6,3,6,3,6,18,
%U 18,9,6,3,18,9,6,3,9,3,6,18,18,9,6,3,18,6,6,3,6,9,6,9,9,3,6,9,18,9,6,9,18
%N a(n) = f^n(n) = f applied n times to n, where f(n) = A007425(n).
%D Amarnath Murthy and Mihaly Bencze [Beneze], Extending the scope of some number theoretic functions, Octogon Mathematical Magazine, 2003, Brasov, Romania.
%H Antti Karttunen, <a href="/A109932/b109932.txt">Table of n, a(n) for n = 1..10000</a>
%t f[n_] := Plus @@ DivisorSigma[0, Divisors[n]]; Table[ Nest[f, n, n], {n, 96}] (* _Robert G. Wilson v_ *)
%o (PARI)
%o A007425(n) = sumdivmult(n, k, numdiv(k)); \\ _Charles R Greathouse IV_, Aug 30 2013
%o A109932(n) = { my(k=n); while(n, n--; k = A007425(k)); k; }; \\ _Antti Karttunen_, Sep 22 2017
%Y Cf. A007425.
%K nonn
%O 1,2
%A _Amarnath Murthy_, Jul 18 2005
%E More terms from _Robert G. Wilson v_, Jul 21 2005
%E Name edited by _Antti Karttunen_, Sep 22 2017
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