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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 6 |
| 8 | 16 |
| 9 | 14 |
| 10 | 34 |
| 11 | 48 |
| 12 | 8448 |
| 13 | 4020 |
| 14 | 9180 |
| 15 | 6272 |
| 16 | 125424 |
| 17 | 846000 |
| 18 | 119448 |
| 19 | 24501600 |
| 20 | 188089566720 |
| 21 | 2828352384 |
| 22 | 132167533680 |
| 23 | 17821427400000 |
| 24 | 459922036392000 |
| 25 | 4085092227635200 |
| 26 | 503568419468083200 |
[1,1,1,1,1,1,2,6,16,14,34,48,8448,4020,9180,6272, 125424,846000,119448,24501600,188089566720, 2828352384,132167533680,17821427400000, 459922036392000,4085092227635200, 503568419468083200] |