A181614 a(n) = number of steps needed to reach a Harshad number when the map k->A062028(l) is iterated starting at n, or -1 if a Harshad number is never reached.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 25, 0, 24, 3, 1, 6, 23, 0, 2, 0, 0, 7, 5, 0, 22, 6, 0, 4, 1, 0, 3, 21, 5, 5, 2, 0, 20, 3, 4, 0, 4, 0, 1, 26, 0, 3, 19, 0, 2, 0, 3, 25, 26, 0, 9, 2, 2, 18, 24, 0, 25, 1, 0, 23, 8, 4, 1, 24, 1, 0, 17, 0, 23, 22, 2, 7, 24, 3, 16, 0, 0, 23, 22, 0

Offset

1,11

References

Eric Angelini, Posting to Sequence Fans Mailing List, Sep 20 2010

Links

Table of n, a(n) for n=1..84.

Hans Havermann, Steps to reach a Harshad

Crossrefs

Cf. A005349, A062028, A181664.

Sequence in context: A255403 A005079 A167624 * A108321 A059062 A179809

Adjacent sequences: A181611 A181612 A181613 * A181615 A181616 A181617

Keyword

nonn,base

Author

N. J. A. Sloane, Nov 18 2010

Extensions

a(22) onward from John W. Layman, Nov 19 2010

Status

approved