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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 7 |
| 5 | 34 |
| 6 | 213 |
| 7 | 1630 |
| 8 | 14747 |
| 9 | 153946 |
| 10 | 1821473 |
| 11 | 24087590 |
| 12 | 352080111 |
| 13 | 5636451794 |
| 14 | 98081813581 |
| 15 | 1843315388078 |
| 16 | 37209072076483 |
| 17 | 802906142007946 |
| 18 | 18443166021077145 |
| 19 | 449326835001457846 |
| 20 | 11572432709175470807 |
| 21 | 314160322966817351938 |
| 22 | 8965995574654847062469 |
[1,1,2,7,34,213,1630,14747,153946,1821473, 24087590,352080111,5636451794,98081813581, 1843315388078,37209072076483,802906142007946, 18443166021077145,449326835001457846, 11572432709175470807,314160322966817351938, 8965995574654847062469] |