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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 12 |
| 3 | 144 |
| 4 | 1644 |
| 5 | 18769 |
| 6 | 169195 |
| 7 | 1525225 |
| 8 | 14158040 |
| 9 | 131423296 |
| 10 | 1263160840 |
| 11 | 12140734225 |
| 12 | 114747871035 |
| 13 | 1084536870921 |
| 14 | 10220222182842 |
| 15 | 96311102247684 |
| 16 | 909854806065252 |
| 17 | 8595434470172356 |
| 18 | 81152480791177280 |
| 19 | 766188743735526400 |
[1,12,144,1644,18769,169195,1525225,14158040, 131423296,1263160840,12140734225,114747871035, 1084536870921,10220222182842,96311102247684, 909854806065252,8595434470172356, 81152480791177280,766188743735526400] |