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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 127 |
| 5 | 126 |
| 6 | 0 |
| 7 | 255256 |
| 8 | 381381 |
| 9 | 126126 |
| 10 | 0 |
| 11 | 2979852651 |
| 12 | 5447453786 |
| 13 | 2956465512 |
| 14 | 488864376 |
| 15 | 0 |
| 16 | 127156445503275 |
| 17 | 264284637872750 |
| 18 | 184292523727620 |
| 19 | 52359004217520 |
| 20 | 5194672859376 |
[1,0,1,0,127,126,0,255256,381381,126126,0, 2979852651,5447453786,2956465512,488864376,0, 127156445503275,264284637872750,184292523727620, 52359004217520,5194672859376] |