A258242 Number of steps from n to 0, where allowable steps are x -> [x/r] if x = is in A022838 (the Beatty sequence for sqrt(3)) and x -> [r*x] otherwise, where [ ] = floor and r = sqrt(3).
0, 1, 3, 2, 4, 4, 3, 5, 5, 7, 5, 7, 4, 6, 8, 6, 8, 8, 10, 6, 8, 10, 5, 7, 7, 9, 11, 7, 9, 9, 11, 9, 11, 13, 7, 9, 9, 11, 11, 6, 8, 8, 10, 8, 10, 10, 12, 14, 8, 10, 10, 10, 12, 12, 14, 10, 12, 12, 14, 16, 8, 10, 10, 12, 10, 12, 14, 12, 14, 7, 9, 9, 9, 11, 11
Offset: 0
Examples
16->27->15->8->4->6->3->1->0, so that a(16) = 8.
Links
- Clark Kimberling, Table of n, a(n) for n = 0..10000
Programs
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Mathematica
r = Sqrt[3]; w = Table[Floor[r*n], {n, 1, 1000}]; f[x_] := If[MemberQ[w, x], Floor[x/r], Floor[r*x]]; g[x_] := Drop[FixedPointList[f, x], -1]; Table[-1+ Length[g[n]], {n, 0, 100}]
Comments