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A308006 Iterate the map x->A308005(x) starting at x=n; a(n) is the number of steps before the first repeated term is encountered. 1
3, 2, 3, 2, 3, 2, 3, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 0, 2, 1, 2, 1, 2, 1, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 1, 2, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Robert Israel, Table of n, a(n) for n = 0..10000

EXAMPLE

0 -> 11 -> 220 -> 33 -> 220 -> ... and a number is repeated at step 4, so a(0)=3.

1 -> 110 -> 231 -> 231 -> 231 -> ..., so a(1) = 2.

22 -> 22 -> 22 -> ... is a fixed point, so a(22) = 0.

MAPLE

# using Maple procedure A308006 from that sequence

f:= proc(n) local t, S, i;

  S:= {n};

  t:= n;

  do

    t:= A308005(t);

    if member(t, S) then return nops(S)-1 fi;

    S:= S union {t};

  od

end proc:

map(f, [$0..100]); # Robert Israel, May 14 2019

CROSSREFS

Cf. A308005.

Sequence in context: A245219 A097509 A095206 * A049071 A168330 A176059

Adjacent sequences:  A308003 A308004 A308005 * A308007 A308008 A308009

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane, May 12 2019

STATUS

approved

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Last modified August 20 07:48 EDT 2019. Contains 326143 sequences. (Running on oeis4.)