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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 25 |
| 5 | 182 |
| 6 | 1256 |
| 7 | 7396 |
| 8 | 39891 |
| 9 | 210384 |
| 10 | 1168317 |
| 11 | 7080023 |
| 12 | 45942141 |
| 13 | 304138329 |
| 14 | 1984289501 |
| 15 | 12627984625 |
| 16 | 79001714951 |
| 17 | 493690545161 |
| 18 | 3127108593615 |
| 19 | 20194195021000 |
| 20 | 132397182653318 |
| 21 | 873218912983165 |
| 22 | 5749093679423621 |
[1,2,5,25,182,1256,7396,39891,210384,1168317, 7080023,45942141,304138329,1984289501,12627984625, 79001714951,493690545161,3127108593615, 20194195021000,132397182653318,873218912983165, 5749093679423621] |