A109932 a(n) = f^n(n) = f applied n times to n, where f(n) = A007425(n).

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

Antti Karttunen, Table of n, a(n) for n = 1..10000

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

Adjacent sequences: A109929 A109930 A109931 * A109933 A109934 A109935

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