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| n | a(n) |
|---|---|
| 1 | 20 |
| 2 | 120 |
| 3 | 209 |
| 4 | 220 |
| 5 | 320 |
| 6 | 420 |
| 7 | 520 |
| 8 | 620 |
| 9 | 720 |
| 10 | 820 |
| 11 | 920 |
| 12 | 1020 |
| 13 | 1120 |
| 14 | 1209 |
| 15 | 1220 |
| 16 | 1320 |
| 17 | 1420 |
| 18 | 1520 |
| 19 | 1620 |
| 20 | 1720 |
| 21 | 1820 |
| 22 | 1920 |
| 23 | 2099 |
| 24 | 2120 |
| 25 | 2209 |
| 26 | 2220 |
| 27 | 2320 |
| 28 | 2420 |
| 29 | 2520 |
| 30 | 2620 |
| 31 | 2720 |
| 32 | 2820 |
| 33 | 2920 |
| 34 | 3020 |
| 35 | 3120 |
| 36 | 3209 |
| 37 | 3220 |
| 38 | 3320 |
| 39 | 3420 |
[20,120,209,220,320,420,520,620,720,820,920,1020, 1120,1209,1220,1320,1420,1520,1620,1720,1820,1920, 2099,2120,2209,2220,2320,2420,2520,2620,2720,2820, 2920,3020,3120,3209,3220,3320,3420] |