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A292635
Numbers n such that 5 applications of "Reverse and Subtract" lead to n, whereas fewer than 5 applications do not lead to n.
9
10591266563195008940873343680499, 27547681086656717245231891334328, 54795638726597554520436127340244, 68723845538328853127615446167114, 88817367774609971118263222539002
OFFSET
1,1
COMMENTS
There are 5 thirty-two-digit terms in the sequence. Further sequences can be obtained by inserting at the center of these terms any number of 9's and by concatenating a term any number of times with itself and inserting an equal number of 0's at all junctures.
LINKS
J. H. E. Cohn, Palindromic differences, Fibonacci Quart. 28 (1990), no. 2, 113-120.
FORMULA
n = f^5(n), n <> f^k(n) for k < 5, where f: x -> |x - reverse(x)|.
EXAMPLE
10591266563195008940873343680499 -> 88817367774609971118263222539002 -> 68723845538328853127615446167114 -> 27547681086656717245231891334328 -> 54795638726597554520436127340244 -> 10591266563195008940873343680499
KEYWORD
nonn,base,more
AUTHOR
EXTENSIONS
Terms ordered by Ray Chandler, Sep 27 2017
STATUS
approved