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A118522 Define sequence S_n by: initial term = n, reverse digits and add 3 to get next term. It is conjectured that S_n always reaches a cycle. Sequence gives number of steps for S_n to reach a cycle.

%I A118522 #12 Jan 16 2018 03:16:00
%S A118522 1,3,3,0,2,2,0,1,1,0,0,0,6,0,0,0,4,0,0,3,0,0,14,0,0,0,4,0,0,3,0,0,11,
%T A118522 5,13,10,3,6,6,1,5,5,4,0,0,4,0,0,0,2,0,0,7,0,0,12,0,0,0,2,0,0,7,0,0,9,
%U A118522 3,11,8,1,4,4,2,3,3,2,0,0,2,0,0,0,6,0,0,5,0,0,10,0,0,0,6,0,0
%N A118522 Define sequence S_n by: initial term = n, reverse digits and add 3 to get next term. It is conjectured that S_n always reaches a cycle. Sequence gives number of steps for S_n to reach a cycle.
%C A118522 Initial cycles have length 3 or 6.
%C A118522 From _Lars Blomberg_, Jan 15 2018: (Start)
%C A118522 For n < 10^8, the only cycles found are the following:
%C A118522   [4,7,10]
%C A118522   [18,84,51]
%C A118522   [29,95,62]
%C A118522   [11,14,44,47,77,80]
%C A118522   [12,24,45,57,78,90]
%C A118522   [15,54,48,87,81,21]
%C A118522   [16,64,49,97,82,31]
%C A118522   [19,94,52,28,85,61]
%C A118522   [22,25,55,58,88,91]
%C A118522   [26,65,59,98,92,32]
%C A118522 The union of all of them has 51 terms (= 3*3 + 7*6): [4, 7, 10, 11, 12, 14, 15, 16, 18, 19, 21, 22, 24, 25, 26, 28, 29, 31, 32, 44, 45, 47, 48, 49, 51, 52, 54, 55, 57, 58, 59, 61, 62, 64, 65, 77, 78, 80, 81, 82, 84, 85, 87, 88, 90, 91, 92, 94, 95, 97, 98] (End)
%H A118522 Lars Blomberg, <a href="/A118522/b118522.txt">Table of n, a(n) for n = 1..10000</a>
%H A118522 N. J. A. Sloane and others, <a href="/wiki/Sequences_of_RADD_type">Sequences of RADD type</a>, OEIS wiki.
%Y A118522 For records see A118523, A118524. Cf. A117831. For S_1, S_2 etc. see A118517-A118521.
%K A118522 nonn,base
%O A118522 1,2
%A A118522 _N. J. A. Sloane_, May 06 2006