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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 21 |
| 3 | 21 |
| 4 | 76 |
| 5 | 351 |
| 6 | 76 |
| 7 | 336 |
| 8 | 7826 |
| 9 | 7826 |
| 10 | 336 |
| 11 | 1560 |
| 12 | 210456 |
| 13 | 1119936 |
| 14 | 210456 |
| 15 | 1560 |
| 16 | 7826 |
| 17 | 6047412 |
| 18 | 181402676 |
| 19 | 181402676 |
| 20 | 6047412 |
| 21 | 7826 |
| 22 | 39996 |
| 23 | 181410426 |
| 24 | 31345666736 |
| 25 | 176319685116 |
| 26 | 31345666736 |
| 27 | 181410426 |
| 28 | 39996 |
| 29 | 210126 |
| 30 | 5597460306 |
[6,21,21,76,351,76,336,7826,7826,336,1560,210456, 1119936,210456,1560,7826,6047412,181402676, 181402676,6047412,7826,39996,181410426, 31345666736,176319685116,31345666736,181410426, 39996,210126,5597460306] |