login
This site is supported by donations to The OEIS Foundation.

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 14 12:04 EST 2019. Contains 329979 sequences. (Running on oeis4.)