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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 9 |
| 3 | 90 |
| 4 | 1001 |
| 5 | 11934 |
| 6 | 149226 |
| 7 | 1931540 |
| 8 | 25662825 |
| 9 | 347993910 |
| 10 | 4796857230 |
| 11 | 67016296620 |
| 12 | 946844533674 |
| 13 | 13505406670700 |
| 14 | 194214400834356 |
| 15 | 2812744285440936 |
| 16 | 40989428837821289 |
| 17 | 600607911737487654 |
| 18 | 8843512890953152230 |
| 19 | 130783058462384959036 |
[1,1,9,90,1001,11934,149226,1931540,25662825, 347993910,4796857230,67016296620,946844533674, 13505406670700,194214400834356,2812744285440936, 40989428837821289,600607911737487654, 8843512890953152230,130783058462384959036] |