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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 44 |
| 4 | 325 |
| 5 | 3110 |
| 6 | 34258 |
| 7 | 436304 |
| 8 | 6246439 |
| 9 | 99637730 |
| 10 | 1747851787 |
| 11 | 33469239848 |
| 12 | 694321125511 |
| 13 | 15513919320368 |
| 14 | 371408549270425 |
| 15 | 9484764686963792 |
| 16 | 257355204923817028 |
| 17 | 7393783957451330630 |
| 18 | 224224270472995407877 |
[1,2,7,44,325,3110,34258,436304,6246439,99637730, 1747851787,33469239848,694321125511, 15513919320368,371408549270425,9484764686963792, 257355204923817028,7393783957451330630, 224224270472995407877] |