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%I #16 May 24 2022 17:54:16
%S 57,59,114,115,118,119,228,229,230,236,237,238,456,458,460,461,465,
%T 472,473,474,476,477,507,513,912,916,917,920,922,930,931,943,944,945,
%U 946,947,948,949,952,954,971,987,1014,1015,1025,1026,1027,1031,1129,1131
%N Numbers with 11 odd integers in their Collatz (or 3x+1) trajectory.
%C The Collatz (or 3x+1) function is f(x) = x/2 if x is even, 3x+1 if x is odd. The Collatz trajectory of n is obtained by applying f repeatedly to n until 1 is reached.
%D J. Shallit and D. Wilson, The "3x+1" Problem and Finite Automata, Bulletin of the EATCS #46 (1992) pp. 182-185.
%H Alois P. Heinz, <a href="/A072466/b072466.txt">Table of n, a(n) for n = 1..10000</a>
%H J. Shallit and D. Wilson, <a href="http://www.cs.uwaterloo.ca/~shallit/Papers/wilson.ps">The "3x+1" Problem and Finite Automata</a>, Bulletin of the EATCS #46 (1992) pp. 182-185.
%H <a href="/index/Ar#2-automatic">Index entries for 2-automatic sequences</a>.
%p b:= proc(n) option remember; irem(n, 2, 'r')+
%p `if`(n=1, 0, b(`if`(n::odd, 3*n+1, r)))
%p end:
%p q:= n-> is(b(n)=11):
%p select(q, [$1..2000])[]; # _Alois P. Heinz_, May 18 2022
%t ocollQ[n_]:=Length[Select[NestWhileList[If[EvenQ[#],#/2,3#+1]&,n,#>1&],OddQ[#]&]]==11; Select[Range[1140],ocollQ[#]&] (* _Jayanta Basu_, May 28 2013 *)
%Y Cf. A062052-A062060.
%Y Column k=11 of A354236.
%K easy,nonn
%O 1,1
%A _Jim Nastos_, Jun 19 2002
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