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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 656 |
| 4 | 64895 |
| 5 | 2263323 |
| 6 | 40728358 |
| 7 | 464160877 |
| 8 | 3788798018 |
| 9 | 23985732786 |
| 10 | 124343403711 |
| 11 | 548683300726 |
| 12 | 2120490369833 |
| 13 | 7334132330405 |
| 14 | 23085114905772 |
| 15 | 67009386720139 |
| 16 | 181293280189204 |
| 17 | 461148470725844 |
[0,1,656,64895,2263323,40728358,464160877, 3788798018,23985732786,124343403711,548683300726, 2120490369833,7334132330405,23085114905772, 67009386720139,181293280189204,461148470725844] |