A072217 Consider the Reverse and Add! problem (cf. A001127); of all the n-digit numbers N which eventually reach a palindrome, pick that number N which takes the greatest number of steps to converge (in case of a tie, pick the smallest N); sequence gives number of steps N takes to converge.

2, 24, 23, 21, 55, 64, 96, 96, 98, 109, 149, 149, 188, 186, 201, 197, 236, 232

Offset: 1

Author

N. J. A. Sloane, Jul 05 2002

Keywords

• nonn
• hard
• base

Comments

Since we do not even know if 196 eventually converges (see A006960, A023108) for n >= 3 these values are only conjectures.

Links

• Jason Doucette, World records
• Index entries for sequences related to Reverse and Add!

Crossrefs

Cf. A072216, A072218, A001127, A006960, A023108.

Extensions

Corrected and extended by Jason Doucette, Mar 29 2005; Oct 09 2005