cp's OEIS Frontend

A257699 Number of steps from n to 0 using this algorithm: x -> floor(r*x) if x is odd, and x -> floor(x/r) if x is even, where r = 5/2.

%I A257699 #4 May 06 2015 09:49:04
%S A257699 2,1,7,3,5,2,6,8,10,4,14,4,6,6,10,3,5,7,13,9,11,9,13,11,13,5,13,15,17,
%T A257699 5,9,5,7,7,13,7,9,11,15,4,6,4,18,6,8,8,12,14,16,10,16,10,12,12,16,10,
%U A257699 12,14,22,12,14,12,16,14,16,6,12,14,16,16,20,16,18
%N A257699 Number of steps from n to 0 using this algorithm:  x -> floor(r*x) if x is odd, and x -> floor(x/r) if x is even, where r = 5/2.
%H A257699 Clark Kimberling, <a href="/A257699/b257699.txt">Table of n, a(n) for n = 1..10000</a>
%e A257699 5->12->4->1->2->0, total of 5 steps, so that a(5) = 5.
%t A257699 r = 5/2; f[x_] := If[OddQ[x], Floor[r *x], Floor[x/r]]
%t A257699 g[x_] := Drop[FixedPointList[f, x], -1];
%t A257699 Table[-1 + Length[g[n]], {n, 1, 200}]
%Y A257699 Cf. A257698, A257700-A257706.
%K A257699 nonn,easy
%O A257699 1,1
%A A257699 _Clark Kimberling_, May 04 2015