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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 46 |
| 4 | 256 |
| 5 | 1510 |
| 6 | 9283 |
| 7 | 58848 |
| 8 | 381963 |
| 9 | 2525916 |
| 10 | 16958498 |
| 11 | 115288674 |
| 12 | 792042589 |
| 13 | 5490312864 |
| 14 | 38352695246 |
| 15 | 269719400974 |
| 16 | 1908059370583 |
| 17 | 13568804436340 |
| 18 | 96942782340802 |
| 19 | 695513575242284 |
| 20 | 5008808999633736 |
| 21 | 36195063931874308 |
| 22 | 262372258663337954 |
[1,2,9,46,256,1510,9283,58848,381963,2525916, 16958498,115288674,792042589,5490312864, 38352695246,269719400974,1908059370583, 13568804436340,96942782340802,695513575242284, 5008808999633736,36195063931874308, 262372258663337954] |