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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 6 |
| 4 | 21 |
| 5 | 60 |
| 6 | 148 |
| 7 | 334 |
| 8 | 702 |
| 9 | 1396 |
| 10 | 2660 |
| 11 | 4880 |
| 12 | 8687 |
| 13 | 15044 |
| 14 | 25470 |
| 15 | 42212 |
| 16 | 68724 |
| 17 | 110000 |
| 18 | 173522 |
| 19 | 269930 |
| 20 | 414812 |
| 21 | 630032 |
| 22 | 947007 |
| 23 | 1409266 |
| 24 | 2078335 |
| 25 | 3038540 |
| 26 | 4407334 |
| 27 | 6344176 |
| 28 | 9068278 |
| 29 | 12874676 |
| 30 | 18164356 |
| 31 | 25472626 |
| 32 | 35519617 |
| 33 | 49259628 |
| 34 | 67964527 |
| 35 | 93308202 |
[0,0,1,6,21,60,148,334,702,1396,2660,4880,8687, 15044,25470,42212,68724,110000,173522,269930, 414812,630032,947007,1409266,2078335,3038540, 4407334,6344176,9068278,12874676,18164356, 25472626,35519617,49259628,67964527,93308202] |