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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 2 |
| 6 | 5 |
| 7 | 15 |
| 8 | 7 |
| 9 | 28 |
| 10 | 126 |
| 11 | 30 |
| 12 | 165 |
| 13 | 198 |
| 14 | 143 |
| 15 | 1001 |
| 16 | 15015 |
| 17 | 3640 |
| 18 | 884 |
| 19 | 7956 |
| 20 | 1938 |
| 21 | 19380 |
| 22 | 203490 |
| 23 | 49742 |
| 24 | 572033 |
| 25 | 980628 |
| 26 | 240350 |
| 27 | 3124550 |
| 28 | 766935 |
| 29 | 188370 |
| 30 | 2731365 |
| 31 | 40970475 |
| 32 | 20160075 |
| 33 | 4962480 |
| 34 | 81880920 |
| 35 | 20173560 |
| 36 | 353037300 |
[1,1,1,3,2,5,15,7,28,126,30,165,198,143,1001, 15015,3640,884,7956,1938,19380,203490,49742, 572033,980628,240350,3124550,766935,188370, 2731365,40970475,20160075,4962480,81880920, 20173560,353037300] |