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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 2 |
| 5 | 4 |
| 6 | 6 |
| 7 | 8 |
| 8 | 16 |
| 9 | 36 |
| 10 | 74 |
| 11 | 136 |
| 12 | 248 |
| 13 | 476 |
| 14 | 946 |
| 15 | 1864 |
| 16 | 3606 |
| 17 | 6948 |
| 18 | 13506 |
| 19 | 26456 |
| 20 | 51856 |
| 21 | 101396 |
| 22 | 198158 |
| 23 | 387976 |
| 24 | 761170 |
| 25 | 1494636 |
| 26 | 2935278 |
| 27 | 5766264 |
| 28 | 11335628 |
| 29 | 22301596 |
| 30 | 43901474 |
| 31 | 86457032 |
| 32 | 170330356 |
| 33 | 335718772 |
| 34 | 661994394 |
| 35 | 1305896760 |
| 36 | 2577024428 |
| 37 | 5087143484 |
| 38 | 10045529338 |
[1,0,0,0,2,4,6,8,16,36,74,136,248,476,946,1864, 3606,6948,13506,26456,51856,101396,198158,387976, 761170,1494636,2935278,5766264,11335628,22301596, 43901474,86457032,170330356,335718772,661994394, 1305896760,2577024428,5087143484,10045529338] |