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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 341 |
| 3 | 13013 |
| 4 | 196053 |
| 5 | 1733303 |
| 6 | 10787231 |
| 7 | 52253971 |
| 8 | 209609235 |
| 9 | 725520510 |
| 10 | 2230238010 |
| 11 | 6217887390 |
| 12 | 15973440990 |
| 13 | 38276304066 |
| 14 | 86383520146 |
| 15 | 185042663146 |
| 16 | 378620563178 |
| 17 | 743881306623 |
| 18 | 1409531082531 |
| 19 | 2585397711611 |
| 20 | 4605062303611 |
[0,1,341,13013,196053,1733303,10787231,52253971, 209609235,725520510,2230238010,6217887390, 15973440990,38276304066,86383520146,185042663146, 378620563178,743881306623,1409531082531, 2585397711611,4605062303611] |