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| n | a(n) |
|---|---|
| 1 | 280 |
| 2 | 1720 |
| 3 | 10344 |
| 4 | 65048 |
| 5 | 395992 |
| 6 | 2497560 |
| 7 | 15235088 |
| 8 | 96142104 |
| 9 | 586688280 |
| 10 | 3702734168 |
| 11 | 22596846536 |
| 12 | 142617229960 |
| 13 | 870368867864 |
| 14 | 5493248738432 |
| 15 | 33524459064760 |
| 16 | 211586539448504 |
| 17 | 1291281038431688 |
| 18 | 8149802725166840 |
[280,1720,10344,65048,395992,2497560,15235088, 96142104,586688280,3702734168,22596846536, 142617229960,870368867864,5493248738432, 33524459064760,211586539448504,1291281038431688, 8149802725166840] |