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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 6 |
| 5 | 14 |
| 6 | 30 |
| 7 | 39 |
| 8 | 28 |
| 9 | 804 |
| 10 | 1620 |
| 11 | 2465 |
| 12 | 15048 |
| 13 | 27642 |
| 14 | 138502 |
| 15 | 360255 |
| 16 | 360120 |
| 17 | 720584 |
| 18 | 8648478 |
| 19 | 12252069 |
| 20 | 208287880 |
| 21 | 232792350 |
| 22 | 232792098 |
| 23 | 232792307 |
| 24 | 2327925312 |
| 25 | 5354228580 |
| 26 | 16062686250 |
| 27 | 26771144049 |
| 28 | 26771143896 |
| 29 | 80313432794 |
[1,1,3,6,14,30,39,28,804,1620,2465,15048,27642, 138502,360255,360120,720584,8648478,12252069, 208287880,232792350,232792098,232792307, 2327925312,5354228580,16062686250,26771144049, 26771143896,80313432794] |