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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 30 |
| 2 | 435 |
| 3 | 4060 |
| 4 | 27405 |
| 5 | 142506 |
| 6 | 593775 |
| 7 | 2035800 |
| 8 | 5852925 |
| 9 | 14307150 |
| 10 | 30045015 |
| 11 | 54627300 |
| 12 | 86493225 |
| 13 | 119759850 |
| 14 | 145422675 |
| 15 | 155117520 |
| 16 | 145422675 |
| 17 | 119759850 |
| 18 | 86493225 |
| 19 | 54627300 |
| 20 | 30045015 |
| 21 | 14307150 |
| 22 | 5852925 |
| 23 | 2035800 |
| 24 | 593775 |
| 25 | 142506 |
| 26 | 27405 |
| 27 | 4060 |
| 28 | 435 |
| 29 | 30 |
| 30 | 1 |
[1,30,435,4060,27405,142506,593775,2035800, 5852925,14307150,30045015,54627300,86493225, 119759850,145422675,155117520,145422675,119759850, 86493225,54627300,30045015,14307150,5852925, 2035800,593775,142506,27405,4060,435,30,1] |