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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 47 |
| 4 | 988 |
| 5 | 18754 |
| 6 | 376200 |
| 7 | 7393463 |
| 8 | 146226480 |
| 9 | 2887603008 |
| 10 | 57051216021 |
| 11 | 1127051412486 |
| 12 | 22265930239751 |
| 13 | 439877330194814 |
| 14 | 8690100341205478 |
| 15 | 171679023552691198 |
| 16 | 3391641194032785411 |
| 17 | 67004275330116215523 |
[0,2,47,988,18754,376200,7393463,146226480, 2887603008,57051216021,1127051412486, 22265930239751,439877330194814,8690100341205478, 171679023552691198,3391641194032785411, 67004275330116215523] |