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| n | a(n) |
|---|---|
| 1 | 11220 |
| 2 | 20864 |
| 3 | 47776 |
| 4 | 164576 |
| 5 | 433296 |
| 6 | 1379208 |
| 7 | 3629540 |
| 8 | 13289252 |
| 9 | 35756268 |
| 10 | 128976744 |
| 11 | 346446144 |
| 12 | 1333284060 |
| 13 | 3588481008 |
| 14 | 13880081488 |
| 15 | 37224984364 |
| 16 | 148837476180 |
| 17 | 398218723908 |
| 18 | 1607711747604 |
| 19 | 4285914451420 |
| 20 | 17630641010960 |
[11220,20864,47776,164576,433296,1379208,3629540, 13289252,35756268,128976744,346446144,1333284060, 3588481008,13880081488,37224984364,148837476180, 398218723908,1607711747604,4285914451420, 17630641010960] |