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A289152 Ordinal transform of A003434. 1
1, 1, 1, 2, 1, 3, 2, 3, 4, 5, 1, 6, 2, 7, 3, 4, 1, 8, 5, 6, 7, 8, 2, 9, 3, 10, 11, 12, 4, 13, 5, 6, 7, 8, 9, 14, 10, 15, 11, 12, 1, 16, 13, 14, 15, 16, 2, 17, 18, 19, 3, 20, 4, 17, 5, 21, 22, 23, 6, 24, 7, 25, 26, 8, 9, 27, 10, 11, 12, 28, 13, 29, 14, 30, 15 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

The ordinal transform mentioned is the one described in A002260: the ordinal transform of a sequence b(n) is the sequence t(n) = number of values in b(1),...,b(n) which are equal to b(n).

This sequence has graphical similarities with A286343.

LINKS

Rémy Sigrist, Table of n, a(n) for n = 1..10000

EXAMPLE

The first terms are:

    n    A003434(n)      a(n)

   --    ----------      ----

    1           0          1

    2           1          1

    3           2          1

    4           2          2

    5           3          1

    6           2          3

    7           3          2

    8           3          3

    9           3          4

   10           3          5

   11           4          1

   12           3          6

   13           4          2

   14           3          7

   15           4          3

   16           4          4

   17           5          1

   18           3          8

   19           4          5

   20           4          6

MATHEMATICA

With[{nn = 75}, Function[s, Table[Count[#, Last@ #] &@ Take[s, n], {n, nn}]]@ Table[Length@ NestWhileList[EulerPhi, n, # != 1 &] - 1, {n, nn}]] (* Michael De Vlieger, Jun 27 2017 *)

PROG

(PARI) A003434(n) = for (k=0, oo, if (n==1, return (k), n=eulerphi(n)))

o = vector(10); for (n=1, 100, v=A003434(n); o[1+v]++; print1(o[1+v] ", "))

CROSSREFS

Cf. A002260, A003434, A286343.

Sequence in context: A029163 A196191 A137661 * A285779 A319320 A305194

Adjacent sequences:  A289149 A289150 A289151 * A289153 A289154 A289155

KEYWORD

nonn,look

AUTHOR

Rémy Sigrist, Jun 26 2017

STATUS

approved

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Last modified November 26 09:38 EST 2020. Contains 338639 sequences. (Running on oeis4.)