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| n | a(n) |
|---|---|
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 8 |
| 7 | 15 |
| 8 | 32 |
| 9 | 64 |
| 10 | 144 |
| 11 | 330 |
| 12 | 768 |
| 13 | 1800 |
| 14 | 4368 |
| 15 | 10800 |
| 16 | 27300 |
| 17 | 70560 |
| 18 | 184800 |
| 19 | 494208 |
| 20 | 1343680 |
| 21 | 3704400 |
| 22 | 10388250 |
| 23 | 29560960 |
| 24 | 85250880 |
| 25 | 249318000 |
| 26 | 738720000 |
| 27 | 2216160000 |
| 28 | 6729074352 |
| 29 | 20675655000 |
| 30 | 64247758848 |
| 31 | 201820667904 |
[1,2,4,8,15,32,64,144,330,768,1800,4368,10800, 27300,70560,184800,494208,1343680,3704400, 10388250,29560960,85250880,249318000,738720000, 2216160000,6729074352,20675655000,64247758848, 201820667904] |