A039502 Iterations of "n->n/2 if n even, n->3n-1 if n odd" (A001281) starting at these numbers reach 17.

17, 21, 23, 25, 31, 33, 34, 37, 41, 42, 45, 46, 49, 50, 55, 61, 62, 66, 67, 68, 73, 74, 82, 83, 84, 90, 91, 92, 98, 99, 100, 109, 110, 111, 117, 122, 123, 124, 131, 132, 134, 136, 146, 147, 148, 153, 163, 164, 165, 166, 168, 175, 179, 180, 182, 184, 185, 195, 196