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A291787
Trajectory of 45 under repeated application of the map k -> A291784(k).
8
45, 48, 56, 60, 80, 88, 92, 94, 95, 96, 112, 120, 160, 176, 184, 188, 190, 216, 252, 324, 378, 486, 567, 594, 738, 876, 1032, 1224, 1488, 1776, 2112, 2624, 2656, 2672, 2680, 2976, 3552, 4224, 5248, 5312, 5344, 5360, 5952, 7104, 8448, 10496, 10624
OFFSET
0,1
COMMENTS
It may be that every trajectory under iteration of the map k -> A291784(k) which increases indefinitely will eventually merge with this sequence. This is certainly true for the terms 45 through 152 of A291788. - N. J. A. Sloane, Sep 24 2017
REFERENCES
Richard K. Guy, Unsolved Problems in Number Theory, 3rd Edition, Springer, 2004. See Section B41, p. 147.
LINKS
N. J. A. Sloane, Three (No, 8) Lovely Problems from the OEIS, Experimental Mathematics Seminar, Rutgers University, Oct 05 2017, Part I, Part 2, Slides. (Mentions this sequence)
C. R. Wall, Unbounded sequences of Euler-Dedekind means, Amer. Math. Monthly, 92 (1985), 587.
FORMULA
a(n) = 2*a(n-7) for n >= 35, which proves this is unbounded. [Guy, Wall]
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Sep 02 2017
EXTENSIONS
More terms from Hugo Pfoertner, Sep 03 2017
STATUS
approved