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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 3 |
| 8 | 1 |
| 9 | 0 |
| 10 | 0 |
| 11 | 5 |
| 12 | 13 |
| 13 | 20 |
| 14 | 13 |
| 15 | 5 |
| 16 | 0 |
| 17 | 0 |
| 18 | 56 |
| 19 | 136 |
| 20 | 221 |
| 21 | 266 |
| 22 | 221 |
| 23 | 136 |
| 24 | 56 |
| 25 | 0 |
| 26 | 0 |
| 27 | 1092 |
[1,0,1,0,0,1,3,1,0,0,5,13,20,13,5,0,0,56,136,221, 266,221,136,56,0,0,1092] |