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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 3 |
| 5 | 7 |
| 6 | 16 |
| 7 | 38 |
| 8 | 94 |
| 9 | 239 |
| 10 | 617 |
| 11 | 1605 |
| 12 | 4190 |
| 13 | 10956 |
| 14 | 28668 |
| 15 | 75037 |
| 16 | 196431 |
| 17 | 514243 |
| 18 | 1346284 |
| 19 | 3524594 |
| 20 | 9227482 |
| 21 | 24157835 |
| 22 | 63246005 |
| 23 | 165580161 |
| 24 | 433494458 |
| 25 | 1134903192 |
| 26 | 2971215096 |
| 27 | 7778742073 |
| 28 | 20365011099 |
| 29 | 53316291199 |
| 30 | 139583862472 |
| 31 | 365435296190 |
| 32 | 956722026070 |
[0,0,0,1,3,7,16,38,94,239,617,1605,4190,10956, 28668,75037,196431,514243,1346284,3524594,9227482, 24157835,63246005,165580161,433494458,1134903192, 2971215096,7778742073,20365011099,53316291199, 139583862472,365435296190,956722026070] |