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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 10 |
| 8 | 29 |
| 9 | 94 |
| 10 | 321 |
| 11 | 1262 |
| 12 | 7231 |
| 13 | 51504 |
| 14 | 415403 |
| 15 | 3863371 |
| 16 | 41121252 |
| 17 | 505066528 |
| 18 | 7638140887 |
| 19 | 140942068334 |
| 20 | 3073652987530 |
| 21 | 79190388734899 |
| 22 | 2405781069528047 |
[1,1,1,1,1,3,10,29,94,321,1262,7231,51504,415403, 3863371,41121252,505066528,7638140887, 140942068334,3073652987530,79190388734899, 2405781069528047] |