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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 8 |
| 7 | 16 |
| 8 | 28 |
| 9 | 56 |
| 10 | 104 |
| 11 | 197 |
| 12 | 369 |
| 13 | 699 |
| 14 | 1331 |
| 15 | 2540 |
| 16 | 4870 |
| 17 | 9354 |
| 18 | 18066 |
| 19 | 34949 |
| 20 | 67788 |
| 21 | 131656 |
| 22 | 256271 |
| 23 | 499498 |
| 24 | 974856 |
| 25 | 1904908 |
| 26 | 3726067 |
| 27 | 7295536 |
| 28 | 14297372 |
| 29 | 28041681 |
| 30 | 55040986 |
| 31 | 108110861 |
| 32 | 212487489 |
| 33 | 417884442 |
| 34 | 822287416 |
[0,0,0,1,2,4,8,16,28,56,104,197,369,699,1331,2540, 4870,9354,18066,34949,67788,131656,256271,499498, 974856,1904908,3726067,7295536,14297372,28041681, 55040986,108110861,212487489,417884442,822287416] |