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| n | a(n) |
|---|---|
| 1 | 12 |
| 2 | 52 |
| 3 | 315 |
| 4 | 1044 |
| 5 | 3296 |
| 6 | 20919 |
| 7 | 217620 |
| 8 | 450296 |
| 9 | 125510644 |
| 10 | 138980066871 |
| 11 | 289898680472 |
| 12 | 3593636117787 |
| 13 | 34812833117460 |
| 14 | 1934468176818608 |
| 15 | 1244148342635075 |
| 16 | 86081645453428848 |
| 17 | 8659539839551787053788 |
| 18 | 138771143651019468539176 |
[12,52,315,1044,3296,20919,217620,450296, 125510644,138980066871,289898680472,3593636117787, 34812833117460,1934468176818608,1244148342635075, 86081645453428848,8659539839551787053788, 138771143651019468539176] |