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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 45 |
| 3 | 889 |
| 4 | 25613 |
| 5 | 977271 |
| 6 | 46586281 |
| 7 | 2669066695 |
| 8 | 178800270009 |
| 9 | 13720918482235 |
| 10 | 1187217400278941 |
| 11 | 114379273346497611 |
| 12 | 12144899525595998821 |
| 13 | 1409261040317551952935 |
| 14 | 177436990866294436727409 |
| 15 | 24094164269339964351367231 |
| 16 | 3510079015962779901366174449 |
| 17 | 546103202348225740056486964467 |
[1,4,45,889,25613,977271,46586281,2669066695, 178800270009,13720918482235,1187217400278941, 114379273346497611,12144899525595998821, 1409261040317551952935,177436990866294436727409, 24094164269339964351367231, 3510079015962779901366174449, 546103202348225740056486964467] |