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A109932
a(n) = f^n(n) = f applied n times to n, where f(n) = A007425(n).
1
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, 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, 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
OFFSET
1,2
REFERENCES
Amarnath Murthy and Mihaly Bencze [Beneze], Extending the scope of some number theoretic functions, Octogon Mathematical Magazine, 2003, Brasov, Romania.
LINKS
MATHEMATICA
f[n_] := Plus @@ DivisorSigma[0, Divisors[n]]; Table[ Nest[f, n, n], {n, 96}] (* Robert G. Wilson v *)
PROG
(PARI)
A007425(n) = sumdivmult(n, k, numdiv(k)); \\ Charles R Greathouse IV, Aug 30 2013
A109932(n) = { my(k=n); while(n, n--; k = A007425(k)); k; }; \\ Antti Karttunen, Sep 22 2017
CROSSREFS
Cf. A007425.
Sequence in context: A225074 A127795 A074724 * A071909 A134662 A145444
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Jul 18 2005
EXTENSIONS
More terms from Robert G. Wilson v, Jul 21 2005
Name edited by Antti Karttunen, Sep 22 2017
STATUS
approved