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| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 15 |
| 3 | 117 |
| 4 | 126 |
| 5 | 270 |
| 6 | 2576 |
| 7 | 8820 |
| 8 | 16560 |
| 9 | 21168 |
| 10 | 46848 |
| 11 | 295245 |
| 12 | 441600 |
| 13 | 846720 |
| 14 | 4078080 |
| 15 | 80663040 |
| 16 | 40590720 |
| 17 | 2173236480 |
| 18 | 4011724800 |
| 19 | 21122906112 |
| 20 | 40915058688 |
| 21 | 274148425728 |
| 22 | 63769149440 |
| 23 | 2707602702336 |
| 24 | 6167442456576 |
| 25 | 21586195906560 |
| 26 | 29798871072768 |
| 27 | 420127895977984 |
| 28 | 631722992467968 |
[13,15,117,126,270,2576,8820,16560,21168,46848, 295245,441600,846720,4078080,80663040,40590720, 2173236480,4011724800,21122906112,40915058688, 274148425728,63769149440,2707602702336, 6167442456576,21586195906560,29798871072768, 420127895977984,631722992467968] |