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%I #8 Apr 16 2016 16:37:59
%S 1,1,1,1,1,1,7,1,1,1,7,1,7,7,1,1,1,1,7,1,7,7,1,1,7,7,1,7,1,1,31,7,7,1,
%T 7,1,7,7,7,1,7,7,7,7,1,7,31,1,7,7,1,7,7,1,31,7,7,7,31,1,31,31,7,7,7,7,
%U 7,7,1,7,1,1,7,7,7,7,1,7,31,7,1,7,1,7,1,1,1,7,1,1,31,1,31,31,7,7,7,7
%N Smallest number in the trajectory of n under repeated application of the map k -> A271497(k).
%C It appears that every number n eventually reaches one of the loops (1,2,3), (7,14,21), (31,62,96), ..., (2^(2m)-1, 2^(2m+1)-2, 3(2^(2m)-1))), ...
%H Chai Wah Wu, <a href="/A271498/b271498.txt">Table of n, a(n) for n = 1..10000</a>
%Y Cf. A271497,
%K nonn,base
%O 1,7
%A _N. J. A. Sloane_, Apr 16 2016