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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 81 |
| 3 | 400 |
| 4 | 32400 |
| 5 | 1705636 |
| 6 | 3648100 |
| 7 | 138156516 |
| 8 | 295496100 |
| 9 | 1055340196 |
| 10 | 1476326929 |
| 11 | 2263475776 |
| 12 | 2323432804 |
| 13 | 2592846400 |
| 14 | 2661528100 |
| 15 | 7036525456 |
| 16 | 10994571025 |
| 17 | 17604513124 |
| 18 | 39415749156 |
| 19 | 61436066769 |
| 20 | 85482555876 |
| 21 | 90526367376 |
| 22 | 97577515876 |
| 23 | 98551417041 |
[1,81,400,32400,1705636,3648100,138156516, 295496100,1055340196,1476326929,2263475776, 2323432804,2592846400,2661528100,7036525456, 10994571025,17604513124,39415749156,61436066769, 85482555876,90526367376,97577515876,98551417041] |