A065213 Numbers which need eight 'Reverse and Add' steps to reach a palindrome.

193, 391, 490, 589, 688, 886, 985, 1993, 1995, 2994, 3991, 4990, 4992, 5991, 6990, 8059, 8149, 8239, 8329, 8419, 8509, 8599, 8689, 8779, 8869, 8959, 9058, 9069, 9089, 9148, 9159, 9179, 9238, 9249, 9269, 9328, 9359, 9418, 9429, 9508, 9519, 9539, 9598

Offset: 1

Author

Klaus Brockhaus, Oct 21 2001

Keywords

• nonn
• base

Comments

The number of steps starts at 0, so palindromes (cf. A002113) are excluded.

Numbers k such that A033665(k) = 8. - Andrew Howroyd, Dec 08 2024

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000
• Index entries for sequences related to Reverse and Add!

Crossrefs

Cf. A002113, A015988, A033665, A065206.

Programs

Mathematica

lenQ[n_]:=Length[NestWhileList[#+FromDigits[Reverse[IntegerDigits[#]]]&, n, #!=FromDigits[Reverse[IntegerDigits[#]]]&,1,10]]==9; Select[Range[ 10000], lenQ] (* Harvey P. Dale, Aug 09 2013 *)

Extensions

Offset changed from 0 to 1 by Harry J. Smith, Oct 14 2009