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A090069
Numbers n such that there are (presumably) eight palindromes in the Reverse and Add! trajectory of n.
2
3, 8, 20, 22, 100, 101, 116, 122, 139, 151, 160, 215, 221, 238, 313, 314, 320, 337, 343, 413, 436, 512, 611, 634, 696, 710, 717, 727, 733, 832, 931, 1004, 1011, 1070, 1101, 1160, 1250, 1340, 1430, 1520, 1610, 1700, 1771, 2000, 2002, 2003, 2010, 2100, 2112
OFFSET
1,1
COMMENTS
For terms <= 5000 each palindrome is reached from the preceding one or from the start in at most 15 steps; after the presumably last one no further palindrome is reached in 2000 steps.
EXAMPLE
The trajectory of 8 begins 8, 16, 77, 154, 605, 1111, 2222, 4444, 8888, 17776, 85547, 160105, 661166, 1322332, 3654563, 7309126, ...; at 7309126 it joins the (presumably) palindrome-free trajectory of A063048(7) = 10577, hence 8, 77, 1111, 2222, 4444, 8888, 661166 and 3654563 are the eight palindromes in the trajectory of 8 and 8 is a term.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Klaus Brockhaus, Nov 20 2003
STATUS
approved