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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 20 |
| 4 | 1070 |
| 5 | 82620 |
| 6 | 7950630 |
| 7 | 893138136 |
| 8 | 113042205894 |
| 9 | 15776443441194 |
| 10 | 2393774318253534 |
| 11 | 391021817774684352 |
| 12 | 68276246115093735882 |
| 13 | 12675272091572931300360 |
| 14 | 2491402163326687657447940 |
[1,1,20,1070,82620,7950630,893138136,113042205894, 15776443441194,2393774318253534, 391021817774684352,68276246115093735882, 12675272091572931300360,2491402163326687657447940] |