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A085928
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a(1) = 1, a(2) = 2, then the absolute difference of the concatenation of two previous terms and its digit reversal.
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0
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1, 2, 9, 63, 594, 14058, 25627437, 5941439657604, 150482558208133815048, 2463743660424402357955859435526447, 5941429767504259381561776919813218438160375943419757604
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| a(n) is a multiple of 99 for n > 4. Conjecture: The sequence has finitely many nonzero terms. (This would happen when the concatenation of two successive terms becomes a palindrome and the next term is 0.)
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EXAMPLE
| a(1) = 1, a(2) = 2, a(3) = |12-21| = 9, a(4) = |29-92| = 63, a(5) = |963-369| = 594, a(6) = |63594 - 49536| = 14058, a(7) = |59418018 - 81081495| = 21663477, ...
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CROSSREFS
| Sequence in context: A100262 A166886 A003577 * A130169 A167913 A076944
Adjacent sequences: A085925 A085926 A085927 * A085929 A085930 A085931
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KEYWORD
| base,nonn
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AUTHOR
| Amarnath Murthy and Jason Earls (amarnath_murthy(AT)yahoo.com), Jul 13 2003
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EXTENSIONS
| Corrected and extended by Mark Hudson (mrmarkhudson(AT)hotmail.com), Jul 23 2004
More terms from David Wasserman (wasserma(AT)spawar.navy.mil), Feb 11 2005
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