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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 25 |
| 2 | 325 |
| 3 | 2950 |
| 4 | 21100 |
| 5 | 126905 |
| 6 | 667850 |
| 7 | 3157725 |
| 8 | 13667175 |
| 9 | 54900675 |
| 10 | 206841715 |
| 11 | 736953800 |
| 12 | 2499500175 |
| 13 | 8113694575 |
| 14 | 25320834800 |
| 15 | 76253908740 |
| 16 | 222308896150 |
| 17 | 629146702350 |
| 18 | 1732518057650 |
| 19 | 4651937973250 |
| 20 | 12201443983695 |
| 21 | 31311905220800 |
| 22 | 78732034002275 |
| 23 | 194220161393825 |
[1,25,325,2950,21100,126905,667850,3157725, 13667175,54900675,206841715,736953800,2499500175, 8113694575,25320834800,76253908740,222308896150, 629146702350,1732518057650,4651937973250, 12201443983695,31311905220800,78732034002275, 194220161393825] |