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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.)