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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 10 |
| 5 | 20 |
| 6 | 36 |
| 7 | 66 |
| 8 | 120 |
| 9 | 219 |
| 10 | 400 |
| 11 | 728 |
| 12 | 1325 |
| 13 | 2413 |
| 14 | 4394 |
| 15 | 8000 |
| 16 | 14564 |
| 17 | 26515 |
| 18 | 48273 |
| 19 | 87884 |
| 20 | 160000 |
| 21 | 291290 |
| 22 | 530312 |
| 23 | 965468 |
| 24 | 1757696 |
| 25 | 3200000 |
| 26 | 5825805 |
| 27 | 10606252 |
| 28 | 19309364 |
| 29 | 35153937 |
| 30 | 64000000 |
| 31 | 116516108 |
[1,1,3,6,10,20,36,66,120,219,400,728,1325,2413, 4394,8000,14564,26515,48273,87884,160000,291290, 530312,965468,1757696,3200000,5825805,10606252, 19309364,35153937,64000000,116516108] |