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

Author

N. J. A. Sloane

Keywords

• nonn
• base

Examples

			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.