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A064745
Inverse permutation to A064736.
2
1, 2, 4, 6, 8, 3, 10, 12, 14, 16, 18, 5, 20, 22, 24, 26, 28, 30, 32, 7, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 9, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 11, 102, 104, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124
OFFSET
1,2
MATHEMATICA
max = 124; ClearAll[a, b]; A064736 = {a[1]=1, a[2]=2}; a[n_] := a[n] = (an = If[OddQ[n], a[n-1]*a[n+1], First[ Complement[ Range[n], A064736]]]; AppendTo[A064736, an]; an); Do[b[a[n]] = n, {n, 1, max}]; A064745 = Table[b[n], {n, 1, a[max]}] (* Jean-François Alcover, Aug 07 2012 *)
PROG
(Haskell)
import Data.List (elemIndex)
import Data.Maybe (fromJust)
a064745 n = fromJust (elemIndex n a064736_list) + 1
-- Reinhard Zumkeller, Mar 23 2012
CROSSREFS
Sequence in context: A355506 A241012 A355213 * A304090 A218454 A115425
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Oct 21 2001
EXTENSIONS
More terms from Vladeta Jovovic, Oct 21 2001
STATUS
approved