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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 12 |
| 4 | 42 |
| 5 | 165 |
| 6 | 3000 |
| 7 | 2142 |
| 8 | 39270 |
| 9 | 838695 |
| 10 | 2185092 |
| 11 | 194467182 |
| 12 | 649154415 |
| 13 | 33547795512 |
| 14 | 40753286805 |
| 15 | 24563658547425 |
| 16 | 1364238471026340 |
| 17 | 2297427262231332 |
| 18 | 1662166966658270160 |
| 19 | 783186317937632697 |
| 20 | 404695317060455732220 |
| 21 | 162293533192142440777455 |
| 22 | 634357227813958501290435 |
[1,3,12,42,165,3000,2142,39270,838695,2185092, 194467182,649154415,33547795512,40753286805, 24563658547425,1364238471026340,2297427262231332, 1662166966658270160,783186317937632697, 404695317060455732220,162293533192142440777455, 634357227813958501290435] |