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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 27 |
| 5 | 122 |
| 6 | 607 |
| 7 | 3208 |
| 8 | 17688 |
| 9 | 99803 |
| 10 | 571238 |
| 11 | 3292738 |
| 12 | 19001315 |
| 13 | 109303307 |
| 14 | 624615928 |
| 15 | 3537913240 |
| 16 | 19843769848 |
| 17 | 110273489737 |
| 18 | 608712132055 |
| 19 | 3355449334452 |
| 20 | 18624818099047 |
| 21 | 105191779542849 |
| 22 | 610586100129734 |
| 23 | 3662333209225714 |
| 24 | 22652502251884322 |
[1,1,2,7,27,122,607,3208,17688,99803,571238, 3292738,19001315,109303307,624615928,3537913240, 19843769848,110273489737,608712132055, 3355449334452,18624818099047,105191779542849, 610586100129734,3662333209225714, 22652502251884322] |