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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 0 |
| 7 | 0 |
| 8 | 1 |
| 9 | 0 |
| 10 | 126 |
| 11 | 1 |
| 12 | 0 |
| 13 | 1287 |
| 14 | 1 |
| 15 | 126126 |
| 16 | 10803 |
| 17 | 1 |
| 18 | 5513508 |
| 19 | 87210 |
| 20 | 488864377 |
| 21 | 175388031 |
| 22 | 698820 |
| 23 | 61841343565 |
| 24 | 5037240879 |
| 25 | 5194678451481 |
| 26 | 5281277511511 |
| 27 | 139251621015 |
| 28 | 1519441856106345 |
| 29 | 387880753064806 |
| 30 | 123382468421090541 |
[1,0,0,0,0,1,0,0,1,0,126,1,0,1287,1,126126,10803, 1,5513508,87210,488864377,175388031,698820, 61841343565,5037240879,5194678451481, 5281277511511,139251621015,1519441856106345, 387880753064806,123382468421090541] |