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%I #6 May 27 2013 03:30:48
%S 3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,
%T 18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,
%U 36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9,3,7,36,18,9
%N Collatz-2 (A063041) trajectory starting at 3.
%C a(0) = a(5) = 3
%F a(0) = 3 and a(n) = A063041(a(n-1)) for n > 0
%t NestList[If[PrimeQ[#],#*Prime[PrimePi[#]-1]+1,#/Min@@First/@FactorInteger[#]]&,3,104] (* _Jayanta Basu_, May 27 2013 *)
%Y A063041.
%K nonn,easy
%O 0,1
%A _Reinhard Zumkeller_, Jul 07 2001