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A232643
Inverse permutation of the sequence of positive integers at A232642.
2
1, 2, 4, 3, 6, 5, 9, 8, 14, 7, 12, 11, 19, 10, 17, 16, 27, 15, 25, 24, 40, 13, 22, 21, 35, 20, 33, 32, 53, 18, 30, 29, 48, 28, 46, 45, 74, 26, 43, 42, 69, 41, 67, 66, 108, 23, 38, 37, 61, 36, 59, 58, 95, 34, 56, 55, 90, 54, 88, 87, 142, 31, 51, 50, 82, 49
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