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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 5 |
| 6 | 17 |
| 7 | 43 |
| 8 | 197 |
| 9 | 1293 |
| 10 | 11263 |
| 11 | 110807 |
| 12 | 1310257 |
| 13 | 21564593 |
| 14 | 459131585 |
| 15 | 12523288493 |
| 16 | 440243859565 |
| 17 | 19398701026043 |
| 18 | 1090842898014815 |
| 19 | 79649624560507867 |
| 20 | 7542069381975617255 |
| 21 | 913933732625520247505 |
[1,1,1,1,5,17,43,197,1293,11263,110807,1310257, 21564593,459131585,12523288493,440243859565, 19398701026043,1090842898014815,79649624560507867, 7542069381975617255,913933732625520247505] |