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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 7 |
| 5 | 14 |
| 6 | 30 |
| 7 | 64 |
| 8 | 141 |
| 9 | 316 |
| 10 | 713 |
| 11 | 1626 |
| 12 | 3740 |
| 13 | 8659 |
| 14 | 20176 |
| 15 | 47274 |
| 16 | 111302 |
| 17 | 263201 |
| 18 | 624860 |
| 19 | 1488736 |
| 20 | 3558412 |
| 21 | 8530533 |
| 22 | 20505468 |
| 23 | 49413242 |
| 24 | 119347708 |
| 25 | 288873639 |
| 26 | 700582008 |
| 27 | 1702190653 |
| 28 | 4142880297 |
| 29 | 10099352082 |
| 30 | 24656876772 |
| 31 | 60283224645 |
| 32 | 147581756005 |
[1,1,2,4,7,14,30,64,141,316,713,1626,3740,8659, 20176,47274,111302,263201,624860,1488736,3558412, 8530533,20505468,49413242,119347708,288873639, 700582008,1702190653,4142880297,10099352082, 24656876772,60283224645,147581756005] |