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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 3 |
| 8 | 8 |
| 9 | 20 |
| 10 | 48 |
| 11 | 136 |
| 12 | 344 |
| 13 | 788 |
| 14 | 1775 |
| 15 | 3947 |
| 16 | 9373 |
| 17 | 21533 |
| 18 | 48327 |
| 19 | 104676 |
| 20 | 224997 |
| 21 | 496490 |
| 22 | 1082575 |
| 23 | 2334984 |
| 24 | 4997364 |
| 25 | 10532236 |
| 26 | 22568064 |
| 27 | 48062489 |
| 28 | 101796210 |
| 29 | 214545469 |
| 30 | 450146443 |
| 31 | 946329292 |
| 32 | 1980769346 |
[0,0,0,0,0,0,1,3,8,20,48,136,344,788,1775,3947, 9373,21533,48327,104676,224997,496490,1082575, 2334984,4997364,10532236,22568064,48062489, 101796210,214545469,450146443,946329292, 1980769346] |