A033909 Number of Sort then Add steps needed to reach a sorted number, or -1 if never reach sorted number.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 3, 2, 0, 0, 0, 0, 1, 1, 1, 3, 2, 2, 2, 0, 0, 0

Offset

0,65

Links

Table of n, a(n) for n=0..79.

Example

64 -> 64+46=110 -> 110+11=121 -> 121+112 = 233, taking 3 steps to reach a sorted number, so a(64)=3.

Crossrefs

Cf. A033863, A033908.

Sequence in context: A134884 A229850 A269162 * A292240 A369932 A324881

Adjacent sequences: A033906 A033907 A033908 * A033910 A033911 A033912

Keyword

nonn,base

Author

N. J. A. Sloane.

Status

approved