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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 21 |
| 7 | 51 |
| 8 | 217 |
| 9 | 1233 |
| 10 | 6449 |
| 11 | 45131 |
| 12 | 442147 |
| 13 | 4714111 |
| 14 | 71906123 |
| 15 | 1148024329 |
| 16 | 26742683865 |
| 17 | 642806579973 |
[1,1,1,1,1,21,51,217,1233,6449,45131,442147, 4714111,71906123,1148024329,26742683865, 642806579973] |