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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 90 |
| 3 | 800 |
| 4 | 7100 |
| 5 | 63000 |
| 6 | 559000 |
| 7 | 4960000 |
| 8 | 44010000 |
| 9 | 390500000 |
| 10 | 3464900000 |
| 11 | 30744000000 |
| 12 | 272791000000 |
| 13 | 2420470000000 |
| 14 | 21476790000000 |
| 15 | 190563200000000 |
| 16 | 1690864100000000 |
| 17 | 15003009000000000 |
| 18 | 133121449000000000 |
| 19 | 1181184400000000000 |
| 20 | 10480629510000000000 |
[1,10,90,800,7100,63000,559000,4960000,44010000, 390500000,3464900000,30744000000,272791000000, 2420470000000,21476790000000,190563200000000, 1690864100000000,15003009000000000, 133121449000000000,1181184400000000000, 10480629510000000000] |