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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 16 |
| 3 | 25 |
| 4 | 505 |
| 5 | 3668 |
| 6 | 30718 |
| 7 | 366292 |
| 8 | 2509523 |
| 9 | 26091488 |
| 10 | 234351923 |
| 11 | 1992122611 |
| 12 | 19022851600 |
| 13 | 163598409399 |
| 14 | 1504760262107 |
| 15 | 13600577455859 |
| 16 | 120731359424594 |
| 17 | 1101615290572263 |
| 18 | 9840525557651890 |
| 19 | 88782728901771783 |
| 20 | 800828577200616792 |
[1,16,25,505,3668,30718,366292,2509523,26091488, 234351923,1992122611,19022851600,163598409399, 1504760262107,13600577455859,120731359424594, 1101615290572263,9840525557651890, 88782728901771783,800828577200616792] |