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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 | 126 |
| 11 | 1 |
| 12 | 792 |
| 13 | 1 |
| 14 | 3718 |
| 15 | 126127 |
| 16 | 15808 |
| 17 | 2450449 |
| 18 | 64702 |
| 19 | 31593277 |
| 20 | 489125360 |
| 21 | 343746937 |
| 22 | 21511079558 |
| 23 | 3435303323 |
| 24 | 588969369056 |
| 25 | 5227461790937 |
| 26 | 13006203613950 |
| 27 | 434431246754441 |
| 28 | 255046847579760 |
| 29 | 21684989820772201 |
| 30 | 128034458842091862 |
[1,0,0,0,0,1,0,1,0,1,126,1,792,1,3718,126127, 15808,2450449,64702,31593277,489125360,343746937, 21511079558,3435303323,588969369056,5227461790937, 13006203613950,434431246754441,255046847579760, 21684989820772201,128034458842091862] |