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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 47 |
| 5 | 217 |
| 6 | 1061 |
| 7 | 5399 |
| 8 | 28337 |
| 9 | 152381 |
| 10 | 835823 |
| 11 | 4660779 |
| 12 | 26357111 |
| 13 | 150872165 |
| 14 | 872878665 |
| 15 | 5098306063 |
| 16 | 30034591105 |
| 17 | 178326873753 |
| 18 | 1066472979083 |
| 19 | 6421120346267 |
| 20 | 38907397325295 |
| 21 | 237182461204097 |
| 22 | 1454326514077709 |
| 23 | 8968048205494983 |
| 24 | 55608797571427793 |
| 25 | 346716786105033077 |
[1,1,3,11,47,217,1061,5399,28337,152381,835823, 4660779,26357111,150872165,872878665,5098306063, 30034591105,178326873753,1066472979083, 6421120346267,38907397325295,237182461204097, 1454326514077709,8968048205494983, 55608797571427793,346716786105033077] |