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Numbers n such that there are (presumably) four palindromes in the Reverse and Add! trajectory of n.
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%I #9 Nov 30 2013 11:48:00

%S 9,19,28,29,37,38,39,46,47,48,56,57,64,65,73,74,75,82,83,84,91,92,93,

%T 110,112,121,124,132,134,135,136,138,144,147,155,164,166,174,182,186,

%U 190,192,211,212,219,223,229,230,231,233,234,235,237,240,243,246,249

%N Numbers n such that there are (presumably) four palindromes in the Reverse and Add! trajectory of n.

%C For terms < 2000 each palindrome is reached from the preceding one or from the start in at most 24 steps; after the presumably last one no further palindrome is reached in 2000 steps.

%H <a href="/index/Res#RAA">Index entries for sequences related to Reverse and Add!</a>

%e The trajectory of 134 begins 134, 565, 1130, 1441, 2882, 5764, 10439, 103840, 152141, 293392, 586784, 1074469, ...; at 1074469 it joins the (presumably) palindrome-free trajectory of A063048(72) = 90379, hence 565, 1441, 2882 and 293392 are the four palindromes in the trajectory of 134 and 134 is a term.

%Y Cf. A023108, A023109, A065001, A070742, A077594.

%K nonn,base

%O 1,1

%A _Klaus Brockhaus_, Nov 20 2003