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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 126 |
| 3 | 421 |
| 4 | 3001 |
| 5 | 5604 |
| 6 | 20393 |
| 7 | 45472 |
| 8 | 102595 |
| 9 | 161277 |
| 10 | 338402 |
| 11 | 489034 |
| 12 | 893944 |
| 13 | 1412682 |
| 14 | 2264545 |
| 15 | 3019845 |
| 16 | 4792281 |
| 17 | 6143391 |
| 18 | 9149646 |
| 19 | 12553350 |
| 20 | 17386054 |
| 21 | 21421963 |
| 22 | 30096986 |
| 23 | 38927373 |
| 24 | 51682575 |
| 25 | 65462507 |
| 26 | 84502439 |
| 27 | 100115923 |
[6,126,421,3001,5604,20393,45472,102595,161277, 338402,489034,893944,1412682,2264545,3019845, 4792281,6143391,9149646,12553350,17386054, 21421963,30096986,38927373,51682575,65462507, 84502439,100115923] |