A292635 Numbers n such that 5 applications of "Reverse and Subtract" lead to n, whereas fewer than 5 applications do not lead to n.

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

Table of n, a(n) for n=1..5.

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

Crossrefs

Cf. A072142, A072143, A072718, A072719, A215669, A292634, A292846, A292856, A292857, A292858, A292859.

Sequence in context: A194566 A194216 A058446 * A095456 A375215 A104319

Adjacent sequences: A292632 A292633 A292634 * A292636 A292637 A292638

Keyword

nonn,base,more

Author

Meritxell Vila Miñana, Sep 20 2017

Extensions

Terms ordered by Ray Chandler, Sep 27 2017

Status

approved