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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 10 |
| 6 | 36 |
| 7 | 322 |
| 8 | 2832 |
| 9 | 27954 |
| 10 | 299260 |
| 11 | 3474482 |
| 12 | 43546872 |
| 13 | 586722162 |
| 14 | 8463487844 |
| 15 | 130214368530 |
| 16 | 2129319003680 |
| 17 | 36889393903794 |
| 18 | 675098760648204 |
| 19 | 13015877566642418 |
| 20 | 263726707757115400 |
| 21 | 5603148830577775218 |
| 22 | 124568968969991162100 |
| 23 | 2892414672938546871250 |
[1,0,0,0,0,10,36,322,2832,27954,299260,3474482, 43546872,586722162,8463487844,130214368530, 2129319003680,36889393903794,675098760648204, 13015877566642418,263726707757115400, 5603148830577775218,124568968969991162100, 2892414672938546871250] |