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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 129 |
| 3 | 1209 |
| 4 | 8856 |
| 5 | 57522 |
| 6 | 348945 |
| 7 | 2031525 |
| 8 | 11531712 |
| 9 | 64438638 |
| 10 | 356590161 |
| 11 | 1961459841 |
| 12 | 10749416568 |
| 13 | 58777575354 |
| 14 | 320956083777 |
| 15 | 1751147966157 |
| 16 | 9549634751424 |
| 17 | 52062358139670 |
| 18 | 283782668909793 |
| 19 | 1546691543230473 |
| 20 | 8429380058864280 |
| 21 | 45938035123043586 |
| 22 | 250345837703068209 |
[6,129,1209,8856,57522,348945,2031525,11531712, 64438638,356590161,1961459841,10749416568, 58777575354,320956083777,1751147966157, 9549634751424,52062358139670,283782668909793, 1546691543230473,8429380058864280, 45938035123043586,250345837703068209] |