the sequence 12,15, 18, 21, 51, 81,... consists of all positive multiples of 3 that contain at least one digit that is a 1. what is the 80th term of this sequence?
1 = 12
2 = 15
3 = 18
4 = 21
5 = 51
6 = 81
7 = 102
8 = 105
9 = 108
10 = 111
11 = 114
12 = 117
13 = 120
14 = 123
15 = 126
16 = 129
17 = 132
18 = 135
19 = 138
20 = 141
21 = 144
22 = 147
23 = 150
24 = 153
25 = 156
26 = 159
27 = 162
28 = 165
29 = 168
30 = 171
31 = 174
32 = 177
33 = 180
34 = 183
35 = 186
36 = 189
37 = 192
38 = 195
39 = 198
40 = 201
41 = 210
42 = 213
43 = 216
44 = 219
45 = 231
46 = 261
47 = 291
48 = 312
49 = 315
50 = 318
51 = 321
52 = 351
53 = 381
54 = 411
55 = 414
56 = 417
57 = 441
58 = 471
59 = 501
60 = 510
61 = 513
62 = 516
63 = 519
64 = 531
65 = 561
66 = 591
67 = 612
68 = 615
69 = 618
70 = 621
71 = 651
72 = 681
73 = 711
74 = 714
75 = 717
76 = 741
77 = 771
78 = 801
79 = 810
80 = 813 - this is the 80th term.
