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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 3 |
| 5 | 0 |
| 6 | 15 |
| 7 | 0 |
| 8 | 104 |
| 9 | 0 |
| 10 | 909 |
| 11 | 0 |
| 12 | 9449 |
| 13 | 0 |
| 14 | 112398 |
| 15 | 0 |
| 16 | 1489410 |
| 17 | 0 |
| 18 | 21562086 |
| 19 | 0 |
| 20 | 336086022 |
| 21 | 0 |
| 22 | 5577242292 |
| 23 | 0 |
| 24 | 97671172836 |
| 25 | 0 |
| 26 | 1792348213025 |
| 27 | 0 |
| 28 | 34268124834495 |
| 29 | 0 |
| 30 | 679376016769260 |
| 31 | 0 |
| 32 | 13911118850603610 |
| 33 | 0 |
| 34 | 293220749128031010 |
| 35 | 0 |
[1,0,1,0,3,0,15,0,104,0,909,0,9449,0,112398,0, 1489410,0,21562086,0,336086022,0,5577242292,0, 97671172836,0,1792348213025,0,34268124834495,0, 679376016769260,0,13911118850603610,0, 293220749128031010,0] |