%I
%S 3,227,14563,932067,59652323,3817748707,244335917283,15637498706147,
%T 1000799917193443,64051194700380387,4099276460824344803,
%U 262353693492758067427,16790636383536516315363,1074600728546337044183267,68774446626965570827729123
%N Odd numbers producing 3 outoforder odd numbers in the Collatz (3x+1) iteration.
%C Sequence A198584 gives the first term of the Collatz sequence having exactly 3 odd numbers. This sequence is the subset of A198584 for which the second odd number is larger than the first. The second odd number is (2^(6*n  2)  1)/3, which always occurs as the third term of the sequence.
%e The number 3 has the Collatz iteration {3, 10, 5, 16, 8, 4, 2, 1}, which has three outoforder odd numbers {3, 5, 1}.
%t Table[(2*(2^(6*n  2)  1)/3  1)/3, {n, 15}]
%o (PARI) a(n)=4^(3*n1)\3*2\3 \\ _Charles R Greathouse IV_, Mar 11 2017
%Y Cf. A198584 (Collatz iterations having 3 odd numbers).
%Y Cf. A228872 (Collatz iterations producing 3 inorder odd numbers).
%K nonn,easy
%O 1,1
%A _T. D. Noe_, Sep 12 2013
