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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 14 |
| 4 | 52 |
| 5 | 42 |
| 6 | 310 |
| 7 | 0 |
| 8 | 684 |
| 9 | 584 |
| 10 | 1092 |
| 11 | 0 |
| 12 | 4788 |
| 13 | 0 |
| 14 | 7320 |
| 15 | 0 |
| 16 | 0 |
| 17 | 3276 |
| 18 | 31314 |
| 19 | 0 |
| 20 | 32004 |
| 21 | 0 |
| 22 | 0 |
| 23 | 0 |
[1,3,14,52,42,310,0,684,584,1092,0,4788,0,7320,0, 0,3276,31314,0,32004,0,0,0] |