A090127 Distinct values of phi(n) in order of appearance as n increases.

1, 2, 4, 6, 10, 12, 8, 16, 18, 22, 20, 28, 30, 24, 36, 40, 42, 46, 32, 52, 58, 60, 48, 66, 44, 70, 72, 78, 54, 82, 64, 56, 88, 96, 100, 102, 106, 108, 112, 110, 80, 126, 84, 130, 136, 138, 92, 120, 148, 150, 156, 104, 132, 162, 166, 172, 116, 178, 180, 144, 160, 190, 192

Offset

1,2

Comments

A permutation of A002202. - Amiram Eldar, Nov 14 2024

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Formula

a(n) = A000010(A210719(n)). - Reinhard Zumkeller, Dec 18 2012

Mathematica

t=Table[EulerPhi[w], {w, 1, 100}]; s=Sort[t]; u=Union[t]; Table[Count[s, Part[u, j]], {j, 1, Length[u]}]; g=Table[Min[Flatten[Position[t, Part[u, j]]]], {j, 1, Length[u]}]; uu=Union[g]; Table[Part[t, Part[uu, j]], {j, 1, Length[g]}]
DeleteDuplicates[EulerPhi[Range[200]]] (* Harvey P. Dale, Jan 20 2013 *)

Prog

(Haskell)
a090127 n = a090127_list !! (n-1)
a090127_list = f a000010_list [] where
  f (x:xs) phis | x `elem` phis = f xs phis
                | otherwise     = x : f xs (x : phis)
-- Reinhard Zumkeller, Dec 18 2012

Crossrefs

Cf. A000010, A002202, A210719.

Sequence in context: A102025 A309374 A226295 * A057910 A336066 A120351

Adjacent sequences: A090124 A090125 A090126 * A090128 A090129 A090130

Keyword

nonn

Author

Labos Elemer, Jan 16 2004

Status

approved