A194081 Smallest m such that A005375(m) = n.

0, 1, 3, 4, 5, 6, 8, 10, 11, 13, 14, 15, 17, 18, 19, 20, 22, 23, 24, 25, 27, 29, 30, 31, 32, 34, 36, 37, 39, 40, 41, 42, 44, 46, 47, 49, 50, 51, 53, 54, 55, 56, 58, 60, 61, 63, 64, 65, 67, 68, 69, 70, 72, 73, 74, 75, 77, 79, 80, 82, 83, 84, 86, 87, 88, 89

Offset: 0

Author

Reinhard Zumkeller, Aug 17 2011

Keywords

• nonn

Comments

A005375(a(n)) = n and A005375(m) <> n for m < a(n).

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 0..10000
• Index entries for Hofstadter-type sequences
• Index entries for sequences from "Goedel, Escher, Bach"

Programs

Haskell

import Data.List (elemIndex)
import Data.Maybe (fromJust)
a194081 n = a194081_list !! n
a194081_list = map (fromJust . (`elemIndex` a005375_list)) [0..]

Mathematica

a[0] := 0; a[n_] := a[n] = a[n] = n - a[a[a[a[n - 1]]]]; Table[Select[Range[0, 199], a[#] == n &][[1]], {n, 0, 65}] (* Alonso del Arte, Aug 17 2011 *)