

A030547


Number of terms (including the initial term) needed to reach a palindrome when the Reverse Then Add! map (x > x + (xwithdigitsreversed)) is repeatedly applied to n, or 1 if a palindrome is never reached.


2



1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 1, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 1, 2, 2, 2, 3, 2, 3, 2, 2, 2, 2, 1, 2, 3, 2, 3, 3, 2, 2, 2, 2, 2, 1, 2, 3, 3, 4, 2, 2, 2, 2, 3, 2, 1, 3, 4, 5, 2, 2, 2, 3, 2, 3, 3, 1, 5, 7, 2, 2, 3, 2, 3, 3, 4, 5, 1, 25, 2, 3, 2, 3, 3, 4, 5, 7, 25
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OFFSET

1,10


COMMENTS

It is conjectured that a(196) is the smallest term equal to 1. See A023108.


REFERENCES

Daniel Lignon, Dictionnaire de (presque) tous les nombres entiers, Ellipses, Paris, 2012, 702 pages. See Entry 196.


LINKS

Table of n, a(n) for n=1..98.
Eric Weisstein's World of Mathematics, 196 Algorithm.


MATHEMATICA

Table[Length@
NestWhileList[# + IntegerReverse[#] &, n, ! PalindromeQ[#] &], {n, 98}] (* Robert Price, Oct 18 2019 *)


CROSSREFS

Cf. A006960, A023108, A063018, etc.
Equals A033665(n) + 1.
Sequence in context: A028950 A094916 A036485 * A254690 A156642 A155124
Adjacent sequences: A030544 A030545 A030546 * A030548 A030549 A030550


KEYWORD

nonn,base


AUTHOR

Eric W. Weisstein


EXTENSIONS

Edited by N. J. A. Sloane, May 09 2015


STATUS

approved



