%I #13 Oct 08 2019 15:04:48
%S 7,18,9,23,58,29,73,183,458,229,573,1433,3583,8958,4479,11198,5599,
%T 13998,6999,17498,8749,21873,54683,136708,68354,34177,85443,213608,
%U 106804,53402,26701,66753,166883,417208,208604,104302,52151,130378,65189,162973,407433,1018583,2546458,1273229,3183073,7957683,19894208,9947104
%N Trajectory of 7 under repeated application of the map in A185452.
%C It is conjectured that this trajectory is unbounded, but this is an open problem.
%D J. C. Lagarias, ed., The Ultimate Challenge: The 3x+1 Problem, Amer. Math. Soc., 2010; see page 89.
%H Rémy Sigrist, <a href="/A185455/b185455.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/3#3x1">Index entries for sequences related to 3x+1 (or Collatz) problem</a>
%p f:=n->if n mod 2 = 0 then n/2 else (5*n+1)/2; fi;
%p T:=proc(n,M) global f; local t1,i; t1:=[n];
%p for i from 1 to M-1 do t1:=[op(t1),f(t1[nops(t1)])]; od: t1; end;
%p T(7,120);
%Y Cf. A185452, A185453, A185454.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Feb 04 2011