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| n | a(n) |
|---|---|
| 5 | 1 |
| 6 | 31 |
| 7 | 337 |
| 8 | 3305 |
| 9 | 27085 |
| 10 | 203278 |
| 11 | 1470470 |
| 12 | 10525307 |
| 13 | 74735025 |
| 14 | 534251602 |
| 15 | 3917281240 |
| 16 | 29620189877 |
| 17 | 230717097457 |
| 18 | 1858373700800 |
| 19 | 15544789470865 |
| 20 | 135021858204377 |
| 21 | 1215283222207344 |
| 22 | 11317462847981403 |
| 23 | 108929278516177839 |
| 24 | 1082642589072326140 |
| 25 | 11099778977689173356 |
[1,31,337,3305,27085,203278,1470470,10525307, 74735025,534251602,3917281240,29620189877, 230717097457,1858373700800,15544789470865, 135021858204377,1215283222207344, 11317462847981403,108929278516177839, 1082642589072326140,11099778977689173356] |