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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 11 |
| 5 | 55 |
| 6 | 337 |
| 7 | 2469 |
| 8 | 21021 |
| 9 | 204083 |
| 10 | 2225455 |
| 11 | 26933707 |
| 12 | 358263257 |
| 13 | 5195425937 |
| 14 | 81580864601 |
| 15 | 1379021735147 |
| 16 | 24967860141019 |
| 17 | 482069363651759 |
| 18 | 9887244178274137 |
| 19 | 214678344941548789 |
| 20 | 4919465708844154821 |
| 21 | 118650412290960022299 |
| 22 | 3004435409327455196783 |
[1,1,3,11,55,337,2469,21021,204083,2225455, 26933707,358263257,5195425937,81580864601, 1379021735147,24967860141019,482069363651759, 9887244178274137,214678344941548789, 4919465708844154821,118650412290960022299, 3004435409327455196783] |