A199817 - OEIS

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A199817

Odd numbers producing 10 even numbers in the Collatz iteration.

%I #11 Mar 30 2012 18:38:26

%S 11,35,113,341

%N Odd numbers producing 10 even numbers in the Collatz iteration.

%t Collatz[n_]:=NestWhileList[If[EvenQ[#],#/2,3 #+1]&,n,#>1&];t={};Do[If[Length[Select[Collatz[n],EvenQ]] == 10,AppendTo[t,n]],{n,1,100000,2}];t

%Y Cf. A131450.

%Y Cf. A199636 (row 10).

%K nonn

%O 1,1

%A _Vincenzo Librandi_, Nov 12 2011