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%I #7 Apr 06 2018 17:38:40
%S 3,142,71,3338,1669,78444,39222,19611,921718,460859,21660374,10830187,
%T 509018790,254509395,11961941566,5980970783,281105626802,140552813401,
%U 6605982229848,3302991114924,1651495557462
%N Trajectory of 3 under map n -> 47n+1 if n odd, n->n/2 if n even.
%t NestList[If[EvenQ[#],#/2,47#+1]&,3,30] (* _Harvey P. Dale_, May 05 2014 *)
%K nonn
%O 0,1
%A _N. J. A. Sloane_.