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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 61 |
| 3 | 1105 |
| 4 | 16025 |
| 5 | 239379 |
| 6 | 3794378 |
| 7 | 64432638 |
| 8 | 1173919350 |
| 9 | 22913136730 |
| 10 | 477859512889 |
| 11 | 10616510910603 |
| 12 | 250501631648359 |
| 13 | 6259150585043685 |
| 14 | 165157651772590340 |
| 15 | 4590337237739801932 |
| 16 | 134066099253229461636 |
| 17 | 4105495811166963962292 |
| 18 | 131552972087266209052875 |
[0,1,61,1105,16025,239379,3794378,64432638, 1173919350,22913136730,477859512889, 10616510910603,250501631648359,6259150585043685, 165157651772590340,4590337237739801932, 134066099253229461636,4105495811166963962292, 131552972087266209052875] |