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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 1 |
| 4 | 8 |
| 5 | 21 |
| 6 | 37 |
| 7 | 79 |
| 8 | 187 |
| 9 | 524 |
| 10 | 864 |
| 11 | 1733 |
| 12 | 3495 |
| 13 | 7140 |
| 14 | 14957 |
| 15 | 32545 |
| 16 | 76552 |
| 17 | 214699 |
| 18 | 352849 |
| 19 | 705703 |
| 20 | 1411435 |
| 21 | 2823020 |
| 22 | 5646717 |
| 23 | 11296065 |
| 24 | 22603592 |
| 25 | 45268779 |
| 26 | 90813855 |
| 27 | 182686296 |
| 28 | 369607874 |
| 29 | 756172623 |
| 30 | 1580555509 |
| 31 | 3439905037 |
[1,3,1,8,21,37,79,187,524,864,1733,3495,7140, 14957,32545,76552,214699,352849,705703,1411435, 2823020,5646717,11296065,22603592,45268779, 90813855,182686296,369607874,756172623,1580555509, 3439905037] |