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a(n)=least k satisfying a(k)=n in A050170.
1

%I #11 Jan 24 2018 14:08:41

%S 1,2,5,3,8,6,21,4,13,11,9,30,7,24,22,71,20,18,16,14,45,12,39,10,33,31,

%T 106,104,29,27,25,82,23,74,72,251,249,70,68,19,62,17,54,15,48,46,163,

%U 161,44,42,40,139,38,36,34,117,115,32,109,107,366,105

%N a(n)=least k satisfying a(k)=n in A050170.

%H Ivan Neretin, <a href="/A050171/b050171.txt">Table of n, a(n) for n = 1..2000</a>

%t terms = 62; (* b = A050170 *) b[1] = 1; b[n_] := b[n] = If[FreeQ[Join[{0}, Array[b, n-1]], f = Floor[b[n-1]/Sqrt[5]]], f, Floor[b[n-1]*Sqrt[5]]]; Table[FirstPosition[Array[b, 6*terms], n], {n, 1, terms}] // Flatten (* _Jean-François Alcover_, Sep 12 2017 *)

%K nonn

%O 1,2

%A _Clark Kimberling_

%E Missing terms inserted by _Jean-François Alcover_, Sep 12 2017