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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 11 |
| 4 | 72 |
| 5 | 545 |
| 6 | 4432 |
| 7 | 38081 |
| 8 | 339266 |
| 9 | 3107841 |
| 10 | 29080910 |
| 11 | 276786032 |
| 12 | 2671136262 |
| 13 | 26076724707 |
| 14 | 257061506994 |
| 15 | 2555287226253 |
| 16 | 25584395476368 |
| 17 | 257780104545994 |
| 18 | 2611791146130284 |
| 19 | 26593326491738879 |
| 20 | 271972643143865548 |
| 21 | 2792566207778712513 |
| 22 | 28776796478486084250 |
[1,2,11,72,545,4432,38081,339266,3107841,29080910, 276786032,2671136262,26076724707,257061506994, 2555287226253,25584395476368,257780104545994, 2611791146130284,26593326491738879, 271972643143865548,2792566207778712513, 28776796478486084250] |