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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 8 |
| 5 | 32 |
| 6 | 138 |
| 7 | 624 |
| 8 | 2922 |
| 9 | 14036 |
| 10 | 68788 |
| 11 | 342584 |
| 12 | 1728812 |
| 13 | 8820864 |
| 14 | 45428616 |
| 15 | 235846688 |
| 16 | 1232970010 |
| 17 | 6485204532 |
| 18 | 34295308230 |
| 19 | 182233431688 |
| 20 | 972493015258 |
| 21 | 5209848971700 |
| 22 | 28008206873944 |
| 23 | 151053157070944 |
| 24 | 817032258098112 |
[1,1,2,8,32,138,624,2922,14036,68788,342584, 1728812,8820864,45428616,235846688,1232970010, 6485204532,34295308230,182233431688,972493015258, 5209848971700,28008206873944,151053157070944, 817032258098112] |