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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 3 |
| 8 | 8 |
| 9 | 13 |
| 10 | 24 |
| 11 | 41 |
| 12 | 98 |
| 13 | 229 |
| 14 | 673 |
| 15 | 1711 |
| 16 | 5548 |
| 17 | 16018 |
| 18 | 61606 |
| 19 | 212821 |
| 20 | 953199 |
| 21 | 3714584 |
| 22 | 18906725 |
| 23 | 85353129 |
| 24 | 504635142 |
| 25 | 2652064148 |
| 26 | 18219772927 |
| 27 | 110274034707 |
| 28 | 872419840249 |
| 29 | 6103743292627 |
| 30 | 55838534314788 |
[1,1,1,1,1,1,3,8,13,24,41,98,229,673,1711,5548, 16018,61606,212821,953199,3714584,18906725, 85353129,504635142,2652064148,18219772927, 110274034707,872419840249,6103743292627, 55838534314788] |