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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 5 |
| 3 | 22 |
| 4 | 105 |
| 5 | 551 |
| 6 | 3125 |
| 7 | 18901 |
| 8 | 120785 |
| 9 | 809956 |
| 10 | 5669525 |
| 11 | 41253125 |
| 12 | 310968905 |
| 13 | 2421594449 |
| 14 | 19434554165 |
| 15 | 160416509794 |
| 16 | 1359425390625 |
| 17 | 11809173506531 |
| 18 | 105013666399445 |
| 19 | 954781355707373 |
| 20 | 8865807366284825 |
| 21 | 83996265859375000 |
| 22 | 811222567266570805 |
| 23 | 7980019803318567233 |
[0,1,5,22,105,551,3125,18901,120785,809956, 5669525,41253125,310968905,2421594449,19434554165, 160416509794,1359425390625,11809173506531, 105013666399445,954781355707373,8865807366284825, 83996265859375000,811222567266570805, 7980019803318567233] |