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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 2 |
| 7 | 2 |
| 8 | 8 |
| 9 | 14 |
| 10 | 36 |
| 11 | 62 |
| 12 | 140 |
| 13 | 252 |
| 14 | 522 |
| 15 | 968 |
| 16 | 1920 |
| 17 | 3600 |
| 18 | 7028 |
| 19 | 13286 |
| 20 | 25704 |
| 21 | 48914 |
| 22 | 94302 |
| 23 | 180314 |
| 24 | 347480 |
| 25 | 666996 |
| 26 | 1286460 |
| 27 | 2477328 |
| 28 | 4785300 |
| 29 | 9240012 |
| 30 | 17879314 |
| 31 | 34604066 |
| 32 | 67076096 |
| 33 | 130084990 |
| 34 | 252579600 |
| 35 | 490722342 |
| 36 | 954306080 |
[0,0,0,0,0,0,2,2,8,14,36,62,140,252,522,968,1920, 3600,7028,13286,25704,48914,94302,180314,347480, 666996,1286460,2477328,4785300,9240012,17879314, 34604066,67076096,130084990,252579600,490722342, 954306080] |