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A182649
Algorithm: x->[rx] if x even, x->[rx-x] if x odd, where r = (1+sqrt(5))/2, []=floor; a(n) is the number of steps from x=n to 0.
4
1, 3, 2, 6, 3, 5, 7, 9, 4, 8, 6, 8, 10, 12, 5, 7, 9, 11, 7, 11, 9, 11, 13, 15, 6, 10, 8, 10, 10, 14, 8, 10, 12, 14, 10, 14, 12, 14, 16, 18, 7, 9, 11, 13, 9, 13, 11, 13, 15, 17, 9, 13, 11, 13, 13, 17, 11, 13, 15, 17, 13, 17, 15, 17, 19, 21, 8, 12, 10
OFFSET
1,2
LINKS
EXAMPLE
8->12->19->11->6->9->5->3->1->0; 9 steps, so that a(8) = 9.
MATHEMATICA
r = GoldenRatio; f[x_] := If[OddQ[x], Floor[x/r], Floor[r*x]];
h[x_] := -1 + Length[Drop[FixedPointList[f, x], -1]];
Table[h[n], {n, 1, 100}] (* Clark Kimberling, May 04 2015 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Nov 26 2010
STATUS
approved