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A241665 Number of iterations of A241663 needed to reach either 0 or 1. 2
1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 2, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 3, 1, 3, 1, 1, 1, 4, 1, 2, 1, 1, 1, 2, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 2, 1, 2, 1, 1, 1, 3, 1, 3, 1, 1, 1, 4, 1, 2, 1, 1, 1, 2, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

COMMENTS

It might be more natural to define the initial terms as a(0) = a(1) = 0 for the sake of recurrence. - Antti Karttunen, Oct 01 2018

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

C. Defant, On Arithmetic Functions Related to Iterates of the Schemmel Totient Functions, J. Int. Seq. 18 (2015) # 15.2.1

Colin Defant, Python program

EXAMPLE

A241663(11)=7, A241663(7)=3, A241663(3)=0. Thus, a(11)=3.

PROG

(Python) See Defant link. Enter m=4, as well as starting and ending values of n. The third string of numbers will be this sequence.

(PARI)

A241663(n) = {my(f = factor(n)); prod(i=1, #f~, if ((f[i, 1] == 2) || (f[i, 1] == 3), 0, f[i, 1]^(f[i, 2]-1)*(f[i, 1]-4))); } \\ From A241663

A241665(n) = { my(s=(1==n)); while(n>1, n = A241663(n); s++); (s); }; \\ Antti Karttunen, Oct 01 2018

CROSSREFS

Cf. A241663, A241668.

Sequence in context: A101491 A276949 A205794 * A175307 A324825 A316557

Adjacent sequences:  A241662 A241663 A241664 * A241666 A241667 A241668

KEYWORD

nonn

AUTHOR

Colin Defant, Apr 26 2014

EXTENSIONS

More terms from Alois P. Heinz, Apr 30 2014

Terms a(88) .. a(105) from Antti Karttunen, Oct 01 2018

STATUS

approved

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Last modified May 16 21:28 EDT 2021. Contains 343951 sequences. (Running on oeis4.)