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A064559 Number of iterations in A064553 to reach a fixed point. 1
0, 0, 0, 0, 1, 0, 2, 0, 0, 1, 1, 0, 3, 2, 1, 0, 1, 0, 1, 1, 2, 1, 2, 0, 1, 3, 0, 2, 2, 1, 1, 0, 1, 1, 2, 0, 4, 1, 3, 1, 3, 2, 2, 1, 1, 2, 1, 0, 2, 1, 1, 3, 2, 0, 1, 2, 1, 2, 1, 1, 2, 1, 2, 0, 3, 1, 2, 1, 2, 2, 3, 0, 2, 4, 1, 1, 2, 3, 3, 1, 0, 3, 1, 2, 1, 2, 2, 1, 2, 1, 3, 2, 1, 1, 1, 0, 4, 2, 1, 1, 1, 1, 3, 3, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

COMMENTS

This is well-defined since A064553(n) <= n.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

FORMULA

a(A003586(n)) = 0.

EXAMPLE

a(12) = 0 as A064553(12) = 12.

a(26) = 3 as A064553(26) = 14, A064553(14) = 10, A064553(10) = 8 and A064553(8) = 8.

MATHEMATICA

b[n_] := b[n] = If[n == 1, 1, Times @@ (PrimePi[#[[1]]]^#[[2]]& /@ FactorInteger[n])];

c[n_] := c[n] = If[n == 1, 1, If[PrimeQ[n], Prime[PrimePi[n] + 1], Times @@ (c[#1]^#2& @@@ FactorInteger[n])]];

A064553[n_] := b[c[n]];

a[n_] := Length[FixedPointList[A064553, n]] - 2;

Array[a, 105] (* Jean-Fran├žois Alcover, Dec 02 2021 *)

PROG

(Scheme) (define (A064559 n) (let ((k (A064553 n))) (if (= k n) 0 (+ 1 (A064559 k))))) ;; Antti Karttunen, Jul 23 2017

CROSSREFS

Cf. A064553.

Sequence in context: A326016 A326033 A029429 * A340998 A336562 A067255

Adjacent sequences:  A064556 A064557 A064558 * A064560 A064561 A064562

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Sep 21 2001

STATUS

approved

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Last modified May 21 09:30 EDT 2022. Contains 353908 sequences. (Running on oeis4.)