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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 22 |
| 3 | 77 |
| 4 | 1376 |
| 5 | 4785 |
| 6 | 85302 |
| 7 | 296605 |
| 8 | 5287360 |
| 9 | 18384737 |
| 10 | 327731030 |
| 11 | 1139557101 |
| 12 | 20314036512 |
| 13 | 70634155537 |
| 14 | 1259142532726 |
| 15 | 4378178086205 |
| 16 | 78046522992512 |
| 17 | 271376407189185 |
| 18 | 4837625283003030 |
| 19 | 16820959067643277 |
| 20 | 299854721023195360 |
| 21 | 1042628085786694001 |
[1,22,77,1376,4785,85302,296605,5287360,18384737, 327731030,1139557101,20314036512,70634155537, 1259142532726,4378178086205,78046522992512, 271376407189185,4837625283003030, 16820959067643277,299854721023195360, 1042628085786694001] |