A072146 Numbers n with property that n sets a new record for the length of the preperiodic part of the 'Reverse and Subtract' trajectory of n.

0, 1, 10, 13, 1011, 1013, 1028, 100103, 100107, 100184, 100368, 100484, 113008, 150703, 10000235, 10000434, 10001104, 10001285, 10001777, 10001788, 10002395, 10002494, 10109075, 1000002787, 1000011068, 1000011159, 1000012729, 1001050344

Offset

1,3

Comments

A072147 gives the corresponding records. Since for small n the last term of the preperiodic part is a palindrome (cf. A072137), this sequence is a weak analog of A065198, which uses 'Reverse and Add'.

Links

Alexander Pesch, May 29 2007, Table of n, a(n) for n = 1..44

Example

The preperiodic part of the trajectory of 13 has length 6: 13 -> 18 -> 63 -> 27 -> 45 -> 9; for k < 13 the preperiodic part has a smaller length (at most 2).

Crossrefs

Cf. A072137, A072147, A065198.

Sequence in context: A075828 A153584 A053612 * A332440 A074674 A241041

Adjacent sequences: A072143 A072144 A072145 * A072147 A072148 A072149

Keyword

base,nonn

Author

Klaus Brockhaus, Jun 24 2002

Extensions

a(19) = 10001777 inserted by Alexander Pesch, May 29 2007

Edited by N. J. A. Sloane, Dec 01 2007

Status

approved