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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 907 |
| 4 | 9007 |
| 5 | 90007 |
| 6 | 900007 |
| 7 | 8000009 |
| 8 | 40000003 |
| 9 | 700000001 |
| 10 | 9000000001 |
| 11 | 40000000003 |
| 12 | 700000000009 |
| 13 | 8000000000009 |
| 14 | 70000000000009 |
| 15 | 940000000000007 |
| 16 | 9000000000000007 |
| 17 | 70000000000000003 |
| 18 | 200000000000000003 |
[0,0,907,9007,90007,900007,8000009,40000003, 700000001,9000000001,40000000003,700000000009, 8000000000009,70000000000009,940000000000007, 9000000000000007,70000000000000003, 200000000000000003] |