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%I #7 Jul 27 2012 16:13:04
%S 3,124,62,31,1272,636,318,159,6520,3260,1630,815,33416,16708,8354,
%T 4177,171258,85629,3510790,1755395,71971196,35985598,17992799,
%U 737704760,368852380,184426190,92213095
%N Trajectory of 3 under map n->41n+1 if n odd, n->n/2 if n even
%t NestList[If[OddQ[#],41#+1,#/2]&,3,30] (* _Harvey P. Dale_, Jul 27 2012 *)
%K nonn
%O 0,1
%A _N. J. A. Sloane_.