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Inverse permutation of the sequence of positive integers at A232640.
2

%I #4 Nov 30 2013 14:09:09

%S 1,2,3,5,4,7,6,10,9,15,8,13,12,20,11,18,17,28,16,26,25,41,14,23,22,36,

%T 21,34,33,54,19,31,30,49,29,47,46,75,27,44,43,70,42,68,67,109,24,39,

%U 38,62,37,60,59,96,35,57,56,91,55,89,88,143,32,52,51,83

%N Inverse permutation of the sequence of positive integers at A232640.

%H Clark Kimberling, <a href="/A232641/b232641.txt">Table of n, a(n) for n = 1..1000</a>

%t z = 14; g[1] = {1}; g[2] = {2}; g[n_] := Riffle[g[n - 1] + 1, 2 g[n - 1] + 1]; j[2] = Join[g[1], g[2]]; j[n_] := Join[j[n - 1], g[n]]; g1[n_] := DeleteDuplicates[DeleteCases[g[n], Alternatives @@ j[n - 1]]];

%t g1[1] = g[1]; g1[2] = g[2]; t = Flatten[Table[g1[n], {n, 1, z}]] (* A232640 *)

%t Table[Length[g1[n]], {n, 1, z}] (* A000045 *)

%t Flatten[Table[Position[t, n], {n, 1, 200}]] (* A232641 *)

%Y Cf. A232559, A232639, A232640, A000045.

%K nonn,easy

%O 1,2

%A _Clark Kimberling_, Nov 28 2013