A050016 a(n)=[ a(n-1)/2 ] if this is not among 0,a(1),...,a(n-2), else a(n)=9*a(n-1).

1, 9, 4, 2, 18, 162, 81, 40, 20, 10, 5, 45, 22, 11, 99, 49, 24, 12, 6, 3, 27, 13, 117, 58, 29, 14, 7, 63, 31, 15, 135, 67, 33, 16, 8, 72, 36, 324, 2916, 1458, 729, 364, 182, 91, 819, 409, 204, 102, 51, 25, 225, 112, 56, 28, 252, 126, 1134