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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 7 |
| 5 | 35 |
| 6 | 121 |
| 7 | 847 |
| 8 | 3907 |
| 9 | 35163 |
| 10 | 202741 |
| 11 | 2230151 |
| 12 | 15430207 |
| 13 | 200592691 |
| 14 | 1619195761 |
| 15 | 24287936415 |
| 16 | 224061282907 |
| 17 | 3809041809419 |
| 18 | 39531606447181 |
| 19 | 751100522496439 |
| 20 | 8661323866026007 |
| 21 | 181887801186546147 |
| 22 | 2307185279184885001 |
| 23 | 53065261421252355023 |
| 24 | 734307168916191403507 |
| 25 | 18357679222904785087675 |
[1,1,1,3,7,35,121,847,3907,35163,202741,2230151, 15430207,200592691,1619195761,24287936415, 224061282907,3809041809419,39531606447181, 751100522496439,8661323866026007, 181887801186546147,2307185279184885001, 53065261421252355023,734307168916191403507, 18357679222904785087675] |