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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 9 |
| 8 | 38 |
| 9 | 131 |
| 10 | 387 |
| 11 | 1025 |
| 12 | 2512 |
| 13 | 5834 |
| 14 | 13152 |
| 15 | 29805 |
| 16 | 71858 |
| 17 | 197325 |
| 18 | 635938 |
| 19 | 2311865 |
| 20 | 8867078 |
| 21 | 34201676 |
| 22 | 129669923 |
| 23 | 479650565 |
| 24 | 1731405819 |
| 25 | 6124746296 |
| 26 | 21382533684 |
| 27 | 74413732788 |
| 28 | 261584276096 |
| 29 | 943601869926 |
| 30 | 3547521313455 |
| 31 | 14045005473985 |
[1,1,1,1,1,1,2,9,38,131,387,1025,2512,5834,13152, 29805,71858,197325,635938,2311865,8867078, 34201676,129669923,479650565,1731405819, 6124746296,21382533684,74413732788,261584276096, 943601869926,3547521313455,14045005473985] |