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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 127 |
| 3 | 91 |
| 4 | 264 |
| 5 | 731 |
| 6 | 2073 |
| 7 | 6750 |
| 8 | 23642 |
| 9 | 80209 |
| 10 | 281982 |
| 11 | 1002046 |
| 12 | 3608377 |
| 13 | 12962477 |
| 14 | 46720095 |
| 15 | 168772741 |
| 16 | 610745581 |
| 17 | 2209961264 |
| 18 | 8001134385 |
| 19 | 28984697206 |
| 20 | 105018572887 |
| 21 | 380523339190 |
| 22 | 1378930510442 |
| 23 | 4997467621045 |
| 24 | 18112318334850 |
[21,127,91,264,731,2073,6750,23642,80209,281982, 1002046,3608377,12962477,46720095,168772741, 610745581,2209961264,8001134385,28984697206, 105018572887,380523339190,1378930510442, 4997467621045,18112318334850] |