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A287877
Start with n and repeatedly apply the powertrain map x -> A133500(x); a(n) is the fixed point that is eventually reached, or -1 if the trajectory never reaches a fixed point.
2
1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 4, 8, 1, 9, 0, 8, 2, 1, 1, 3, 9, 8, 8, 0, 2, 0, 0, 0, 1, 4, 1, 0, 2, 1, 0, 0, 0, 0, 1, 5, 9, 5, 0, 0, 0, 0, 0, 0, 1, 6, 2, 1, 0, 0, 0, 0, 0, 0, 1, 7, 0, 0, 0, 7, 0, 0, 0, 0, 1, 8, 0, 1, 0, 0, 0, 0, 0, 0, 1, 9, 8, 2, 0, 0, 0, 0, 0, 0, 0, 1
OFFSET
1,2
COMMENTS
It is conjectured that a fixed point is always reached.
It is also conjectured that the only fixed points are the numbers 0 through 9, 2592, and 24547284284866560000000000 (see A135385).
CROSSREFS
Sequence in context: A346511 A177894 A376771 * A175398 A175401 A175400
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jun 16 2017
STATUS
approved