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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 25 |
| 3 | 441 |
| 4 | 7056 |
| 5 | 108900 |
| 6 | 1656369 |
| 7 | 25050025 |
| 8 | 378224704 |
| 9 | 5712638724 |
| 10 | 86394844900 |
| 11 | 1308887012356 |
| 12 | 19868414760000 |
| 13 | 302198588499600 |
| 14 | 4605510959127225 |
| 15 | 70321771565375625 |
| 16 | 1075697380745222400 |
| 17 | 16483023079048102500 |
| 18 | 252980753801047064100 |
| 19 | 3888662839165553120100 |
[1,25,441,7056,108900,1656369,25050025,378224704, 5712638724,86394844900,1308887012356, 19868414760000,302198588499600,4605510959127225, 70321771565375625,1075697380745222400, 16483023079048102500,252980753801047064100, 3888662839165553120100] |