OFFSET
1,2
LINKS
Clark Kimberling and Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 (first 1000 terms from Clark Kimberling)
MATHEMATICA
z = 14; g[1] = {1}; g[2] = {2}; g[n_] := Riffle[g[n - 1] + 1, 2 g[n - 1] + 2]; 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}]] (* A232642 *)
Table[Length[g1[n]], {n, 1, z}] (* A000045 *)
Flatten[Table[Position[t, n], {n, 1, 200}]] (* A232643 *)
PROG
(Haskell)
import Data.List (elemIndex); import Data.Maybe (fromJust)
a232643 = (+ 1) . fromJust . (`elemIndex` a232642_list)
-- Reinhard Zumkeller, May 14 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Nov 28 2013
EXTENSIONS
b-File corrected by Reinhard Zumkeller, May 14 2015
STATUS
approved