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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 7 |
| 4 | 29 |
| 5 | 121 |
| 6 | 649 |
| 7 | 5041 |
| 8 | 42909 |
| 9 | 364561 |
| 10 | 3515651 |
| 11 | 39916801 |
| 12 | 486821873 |
| 13 | 6227020801 |
| 14 | 86497214231 |
| 15 | 1307843292757 |
| 16 | 21004582611869 |
| 17 | 355687428096001 |
| 18 | 6390006277567483 |
| 19 | 121645100408832001 |
| 20 | 2435277595236694779 |
| 21 | 51091124681475552961 |
| 22 | 1123451899297248225431 |
[1,1,7,29,121,649,5041,42909,364561,3515651, 39916801,486821873,6227020801,86497214231, 1307843292757,21004582611869,355687428096001, 6390006277567483,121645100408832001, 2435277595236694779,51091124681475552961, 1123451899297248225431] |