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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 0 |
| 4 | 17 |
| 5 | 0 |
| 6 | 408 |
| 7 | 0 |
| 8 | 69473 |
| 9 | 0 |
| 10 | 6018928 |
| 11 | 0 |
| 12 | 1363916728 |
| 13 | 0 |
| 14 | 219434809664 |
| 15 | 0 |
| 16 | 184186824259233 |
| 17 | 0 |
| 18 | 57411426894898072 |
| 19 | 0 |
| 20 | 38606038922780709192 |
| 21 | 0 |
| 22 | 16136153318586799828504 |
| 23 | 0 |
| 24 | 20401945614919621585224136 |
| 25 | 0 |
| 26 | 12864310266687158415460633528 |
| 27 | 0 |
[1,1,1,0,17,0,408,0,69473,0,6018928,0,1363916728, 0,219434809664,0,184186824259233,0, 57411426894898072,0,38606038922780709192,0, 16136153318586799828504,0, 20401945614919621585224136,0, 12864310266687158415460633528,0] |