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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 90 |
| 3 | 252 |
| 4 | 1872 |
| 5 | 4464 |
| 6 | 29250 |
| 7 | 62946 |
| 8 | 393912 |
| 9 | 809442 |
| 10 | 4945140 |
| 11 | 9899910 |
| 12 | 59366286 |
| 13 | 116999892 |
| 14 | 692936460 |
| 15 | 1349989992 |
| 16 | 7919601912 |
| 17 | 15299999856 |
| 18 | 89099130960 |
| 19 | 170999999838 |
| 20 | 989995038012 |
| 21 | 1889999872488 |
| 22 | 10889990099100 |
| 23 | 20699999999802 |
| 24 | 118799939782206 |
| 25 | 224999999981964 |
[9,90,252,1872,4464,29250,62946,393912,809442, 4945140,9899910,59366286,116999892,692936460, 1349989992,7919601912,15299999856,89099130960, 170999999838,989995038012,1889999872488, 10889990099100,20699999999802,118799939782206, 224999999981964] |