OFFSET
1,2
LINKS
Clark Kimberling, Table of n, a(n) for n = 1..1000
MATHEMATICA
z = 8; g[1] = {1}; g[2] = {2, 4}; g[n_] := Riffle[g[n - 1] + 1, 4 g[n - 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]]]; g1[1] = g[1]; g1[2] = g[2]; t = Flatten[Table[g1[n], {n, 1, z}]] (* A232563 *)
Table[Length[g1[n]], {n, 1, z}] (* A001631 *)
t1 = Flatten[Table[Position[t, n], {n, 1, 200}]] (* A232564 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Nov 26 2013
STATUS
approved