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| n | a(n) |
|---|---|
| 1 | 40 |
| 2 | 1600 |
| 3 | 2160 |
| 4 | 18096 |
| 5 | 111584 |
| 6 | 592968 |
| 7 | 3773248 |
| 8 | 22906752 |
| 9 | 133271316 |
| 10 | 813048132 |
| 11 | 4888530112 |
| 12 | 29063550656 |
| 13 | 175651306248 |
| 14 | 1052837316972 |
| 15 | 6299856462528 |
| 16 | 37944438834000 |
| 17 | 227332237482360 |
| 18 | 1363281172707168 |
| 19 | 8196861050785472 |
[40,1600,2160,18096,111584,592968,3773248, 22906752,133271316,813048132,4888530112, 29063550656,175651306248,1052837316972, 6299856462528,37944438834000,227332237482360, 1363281172707168,8196861050785472] |