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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 13 |
| 3 | 170 |
| 4 | 2223 |
| 5 | 29069 |
| 6 | 380120 |
| 7 | 4970629 |
| 8 | 64998297 |
| 9 | 849948490 |
| 10 | 11114328667 |
| 11 | 145336221161 |
| 12 | 1900485203760 |
| 13 | 24851643870041 |
| 14 | 324971855514293 |
| 15 | 4249485765555850 |
| 16 | 55568286807740343 |
| 17 | 726637214266180309 |
| 18 | 9501852072268084360 |
| 19 | 124250714153751276989 |
| 20 | 1624761136071034685217 |
[0,1,13,170,2223,29069,380120,4970629,64998297, 849948490,11114328667,145336221161,1900485203760, 24851643870041,324971855514293,4249485765555850, 55568286807740343,726637214266180309, 9501852072268084360,124250714153751276989, 1624761136071034685217] |