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The eventual period of the RATS sequence in base n starting from 1; 0 is for infinity.
3

%I #6 Jun 15 2017 17:11:21

%S 1,3,2,2,8,4,3,2,0,28,90,8,72,3,4,2,64,0,18,4,18,20,396,8,160,120,18,

%T 6,28,4,5,2,210,384,240,0,648,1242,240,4,660,18,798,380,852,1298,1771,

%U 8,0,160,16,372,520,1404,1740,6,36,2072,1856,380,300,215,6,2,3384,50,2310,3784,2904

%N The eventual period of the RATS sequence in base n starting from 1; 0 is for infinity.

%C Eventual period of 1 under the mapping x->A288535(n,x), or 0 if there is a divergence and thus no eventual period.

%C Column 1 of A288537.

%C In Thiel's terms, the zeroes a(10), a(19), and a(37) correspond to quasiperiodic divergent RATS sequences with quasiperiod 2, while a(50)=0 corresponds to a sequence with quasiperiod 3.

%H S. Shattuck and C. Cooper, <a href="http://www.fq.math.ca/Scanned/39-2/shattuck.pdf">Divergent RATS sequences</a>, Fibonacci Quart., 39 (2001), 101-106.

%H J. Thiel, <a href="https://www.emis.de/journals/INTEGERS/papers/o50/o50.pdf">On RATS sequences in general bases</a>, Integers, 14 (2014), #A50.

%H <a href="/index/Ra#RATS">Index entries for sequences related to RATS: Reverse, Add Then Sort</a>

%e In base 3, the RATS mapping acts as 1 -> 2 -> 4 (11 in base 3) -> 8 (22 in base 3) -> 13 (112 in base 3) -> 4, which has already been seen 3 steps ago, so a(3)=3.

%Y Cf. A004000, A114611, A288535, A288537, A237671, A072137.

%K nonn,base

%O 2,2

%A _Andrey Zabolotskiy_, Jun 11 2017