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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 15 |
| 6 | 24 |
| 7 | 35 |
| 8 | 119 |
| 9 | 504 |
| 10 | 720 |
| 11 | 2519 |
| 12 | 2519 |
| 13 | 41040 |
| 14 | 83160 |
| 15 | 83160 |
| 16 | 196559 |
| 17 | 524160 |
| 18 | 524160 |
| 19 | 3160079 |
| 20 | 3160079 |
| 21 | 3160079 |
| 22 | 3160079 |
| 23 | 68468400 |
| 24 | 68468400 |
| 25 | 68468400 |
| 26 | 68468400 |
| 27 | 4724319600 |
| 28 | 4724319600 |
| 29 | 26702675999 |
| 30 | 26702675999 |
[1,1,2,3,15,24,35,119,504,720,2519,2519,41040, 83160,83160,196559,524160,524160,3160079,3160079, 3160079,3160079,68468400,68468400,68468400, 68468400,4724319600,4724319600,26702675999, 26702675999] |