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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 0 |
| 7 | 1 |
| 8 | 0 |
| 9 | 1 |
| 10 | 252 |
| 11 | 1 |
| 12 | 1584 |
| 13 | 1 |
| 14 | 7436 |
| 15 | 756757 |
| 16 | 31616 |
| 17 | 14702689 |
| 18 | 129404 |
| 19 | 189559657 |
| 20 | 11733266992 |
| 21 | 2062481617 |
| 22 | 516242875084 |
| 23 | 20611819933 |
| 24 | 14135172627712 |
| 25 | 623557476714481 |
| 26 | 312148517693820 |
| 27 | 52096977907924561 |
| 28 | 6121122865591920 |
[1,0,0,0,0,1,0,1,0,1,252,1,1584,1,7436,756757, 31616,14702689,129404,189559657,11733266992, 2062481617,516242875084,20611819933, 14135172627712,623557476714481,312148517693820, 52096977907924561,6121122865591920] |