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| n | a(n) |
|---|---|
| 2 | 3 |
| 3 | 6 |
| 4 | 15 |
| 5 | 52 |
| 6 | 245 |
| 7 | 1446 |
| 8 | 10087 |
| 9 | 80648 |
| 10 | 725769 |
| 11 | 7257610 |
| 12 | 79833611 |
| 13 | 958003212 |
| 14 | 12454041613 |
| 15 | 174356582414 |
| 16 | 2615348736015 |
| 17 | 41845579776016 |
| 18 | 711374856192017 |
| 19 | 12804747411456018 |
| 20 | 243290200817664019 |
| 21 | 4865804016353280020 |
| 22 | 102181884343418880021 |
| 23 | 2248001455555215360022 |
| 24 | 51704033477769953280023 |
| 25 | 1240896803466478878720024 |
[3,6,15,52,245,1446,10087,80648,725769,7257610, 79833611,958003212,12454041613,174356582414, 2615348736015,41845579776016,711374856192017, 12804747411456018,243290200817664019, 4865804016353280020,102181884343418880021, 2248001455555215360022,51704033477769953280023, 1240896803466478878720024] |