The rule for this sequence is n + 3. 132 --> 135 is +3, 135 --> 138 is +3, and 138 --> 141 is +3. Let's use this rule until we find the 13th term. 132 (1) 135(2) 138(3) 141(4) 144(5) 147(6) 150(7) 153(8) 156(9) 159(10) 162(11) 165(12) 168(13) 168 is the 13th term in this sequence. I hope this helps!