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A073143 Numbers k such that A073142(n) = f^k(A073142(n)), where f: m -> |m - reverse(m)|. 3
1, 2, 14, 22, 12 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Presumably a(6) = 17. a(n) is the length of the periodic part (cf. A072137) of the trajectory of A073142(n). Question: Does every k > 0 appear in this sequence?

LINKS

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

EXAMPLE

a(3) = 14 since A073142(2) = 11436678 is the smallest solution of x = f^14(x).

CROSSREFS

Cf. A072137, A072141, A072142, A072143, A072718, A072719, A073142, A073144.

Sequence in context: A140578 A052213 A086263 * A066613 A074312 A061426

Adjacent sequences:  A073140 A073141 A073142 * A073144 A073145 A073146

KEYWORD

base,more,nonn

AUTHOR

Klaus Brockhaus, Jul 17 2002

EXTENSIONS

Offset changed by N. J. A. Sloane, Dec 01 2007

STATUS

approved

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Last modified December 3 20:40 EST 2016. Contains 278745 sequences.