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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 14 |
| 3 | 70 |
| 4 | 196 |
| 5 | 640 |
| 6 | 2248 |
| 7 | 6480 |
| 8 | 19072 |
| 9 | 56000 |
| 10 | 169792 |
| 11 | 466560 |
| 12 | 1327104 |
| 13 | 3642880 |
| 14 | 10030080 |
| 15 | 27776000 |
| 16 | 74541056 |
| 17 | 199065600 |
| 18 | 531505152 |
| 19 | 1401405440 |
| 20 | 3672801280 |
| 21 | 9674588160 |
| 22 | 25018564608 |
| 23 | 64701071360 |
| 24 | 166363136000 |
| 25 | 426159636480 |
| 26 | 1084287352832 |
| 27 | 2756737761280 |
| 28 | 6979072294912 |
[1,5,14,70,196,640,2248,6480,19072,56000,169792, 466560,1327104,3642880,10030080,27776000,74541056, 199065600,531505152,1401405440,3672801280, 9674588160,25018564608,64701071360,166363136000, 426159636480,1084287352832,2756737761280, 6979072294912] |