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

%I A090127 #19 Nov 14 2024 05:57:39
%S A090127 1,2,4,6,10,12,8,16,18,22,20,28,30,24,36,40,42,46,32,52,58,60,48,66,
%T A090127 44,70,72,78,54,82,64,56,88,96,100,102,106,108,112,110,80,126,84,130,
%U A090127 136,138,92,120,148,150,156,104,132,162,166,172,116,178,180,144,160,190,192
%N A090127 Distinct values of phi(n) in order of appearance as n increases.
%C A090127 A permutation of A002202. - _Amiram Eldar_, Nov 14 2024
%H A090127 Reinhard Zumkeller, <a href="/A090127/b090127.txt">Table of n, a(n) for n = 1..10000</a>
%F A090127 a(n) = A000010(A210719(n)). - _Reinhard Zumkeller_, Dec 18 2012
%t A090127 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]}]
%t A090127 DeleteDuplicates[EulerPhi[Range[200]]] (* _Harvey P. Dale_, Jan 20 2013 *)
%o A090127 (Haskell)
%o A090127 a090127 n = a090127_list !! (n-1)
%o A090127 a090127_list = f a000010_list [] where
%o A090127   f (x:xs) phis | x `elem` phis = f xs phis
%o A090127                 | otherwise     = x : f xs (x : phis)
%o A090127 -- _Reinhard Zumkeller_, Dec 18 2012
%Y A090127 Cf. A000010, A002202, A210719.
%K A090127 nonn
%O A090127 1,2
%A A090127 _Labos Elemer_, Jan 16 2004