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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 10 |
| 3 | 107 |
| 4 | 1140 |
| 5 | 12149 |
| 6 | 129470 |
| 7 | 1379743 |
| 8 | 14703720 |
| 9 | 156695401 |
| 10 | 1669880050 |
| 11 | 17795668307 |
| 12 | 189645843420 |
| 13 | 2021028112349 |
| 14 | 21537802027430 |
| 15 | 229525217060743 |
| 16 | 2446016784799440 |
| 17 | 26066844367419601 |
| 18 | 277790561167792090 |
| 19 | 2960373522249858107 |
| 20 | 31548269150673125700 |
[0,1,10,107,1140,12149,129470,1379743,14703720, 156695401,1669880050,17795668307,189645843420, 2021028112349,21537802027430,229525217060743, 2446016784799440,26066844367419601, 277790561167792090,2960373522249858107, 31548269150673125700] |