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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1025 |
| 3 | 60074 |
| 4 | 1108650 |
| 5 | 10874275 |
| 6 | 71340451 |
| 7 | 353815700 |
| 8 | 1427557524 |
| 9 | 4914341925 |
| 10 | 14914341925 |
| 11 | 40851766526 |
| 12 | 102769130750 |
| 13 | 240627622599 |
| 14 | 529882277575 |
| 15 | 1106532668200 |
| 16 | 2206044295976 |
| 17 | 4222038196425 |
| 18 | 7792505423049 |
| 19 | 13923571680850 |
[0,1,1025,60074,1108650,10874275,71340451, 353815700,1427557524,4914341925,14914341925, 40851766526,102769130750,240627622599, 529882277575,1106532668200,2206044295976, 4222038196425,7792505423049,13923571680850] |