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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 20 |
| 3 | 165 |
| 4 | 1814 |
| 5 | 25215 |
| 6 | 422800 |
| 7 | 8284753 |
| 8 | 185549202 |
| 9 | 4672333603 |
| 10 | 130609758204 |
| 11 | 4012046505613 |
| 12 | 134303337007166 |
| 13 | 4865394495960599 |
| 14 | 189626416079163448 |
| 15 | 7910956276398901049 |
| 16 | 351720053331418595386 |
| 17 | 16600716065137840118363 |
[3,20,165,1814,25215,422800,8284753,185549202, 4672333603,130609758204,4012046505613, 134303337007166,4865394495960599, 189626416079163448,7910956276398901049, 351720053331418595386,16600716065137840118363] |