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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 25 |
| 2 | 408 |
| 3 | 5558 |
| 4 | 68999 |
| 5 | 813603 |
| 6 | 9315286 |
| 7 | 104854096 |
| 8 | 1168677477 |
| 9 | 12952000061 |
| 10 | 143075613044 |
| 11 | 1577575222314 |
| 12 | 17376397872835 |
| 13 | 191281848531799 |
| 14 | 2104964417048082 |
| 15 | 23159869359140612 |
| 16 | 254790508985373473 |
| 17 | 2802889182202991217 |
| 18 | 30832952040578234800 |
| 19 | 339169546346404999390 |
[1,25,408,5558,68999,813603,9315286,104854096, 1168677477,12952000061,143075613044,1577575222314, 17376397872835,191281848531799,2104964417048082, 23159869359140612,254790508985373473, 2802889182202991217,30832952040578234800, 339169546346404999390] |