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A065320
53 'Reverse and Add' steps are needed to reach a palindrome.
10
10677, 11667, 12657, 13647, 14637, 15627, 16617, 17607, 20676, 21666, 22656, 23646, 24636, 25626, 26616, 27606, 30675, 31665, 32655, 33645, 34635, 35625, 36615, 37605, 40674, 41664, 42654, 43644, 44634, 45624, 46614, 47604, 50673
OFFSET
1,1
COMMENTS
The number of steps starts at 0, so palindromes (cf. A002113) are excluded. 53 is a record (cf. A065199) of the number of 'Reverse and Add' steps needed to reach a palindrome.
The first term not congruent 84 mod 99 is a(64) = 109902, thereafter the residues show no obvious pattern. - Klaus Brockhaus, Jul 14 2003
MATHEMATICA
lenQ[n_]:= Length[NestWhileList[# + FromDigits[Reverse[IntegerDigits[#]]]&, n, #! = FromDigits[Reverse[IntegerDigits[#]]]&, 1, 54]] == 54; Select[Range[10000], lenQ] (* Vincenzo Librandi, Sep 24 2013 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Klaus Brockhaus, Oct 30 2001
EXTENSIONS
Changed offset from 0 to 1 by Vincenzo Librandi, Sep 24 2013
STATUS
approved