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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 10 |
| 4 | 29 |
| 5 | 63 |
| 6 | 164 |
| 7 | 339 |
| 8 | 797 |
| 9 | 1640 |
| 10 | 3578 |
| 11 | 7139 |
| 12 | 15210 |
| 13 | 29621 |
| 14 | 60381 |
| 15 | 117116 |
| 16 | 232523 |
| 17 | 442388 |
| 18 | 863069 |
| 19 | 1621560 |
| 20 | 3105993 |
| 21 | 5785525 |
| 22 | 10894394 |
| 23 | 20083143 |
| 24 | 37434186 |
| 25 | 68344449 |
| 26 | 125774280 |
| 27 | 228088127 |
| 28 | 415668548 |
| 29 | 747660318 |
| 30 | 1351364816 |
| 31 | 2413792653 |
| 32 | 4327245170 |
[0,1,4,10,29,63,164,339,797,1640,3578,7139,15210, 29621,60381,117116,232523,442388,863069,1621560, 3105993,5785525,10894394,20083143,37434186, 68344449,125774280,228088127,415668548,747660318, 1351364816,2413792653,4327245170] |