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| n | a(n) |
|---|---|
| 1 | 16 |
| 2 | 256 |
| 3 | 704 |
| 4 | 2816 |
| 5 | 10144 |
| 6 | 38208 |
| 7 | 140032 |
| 8 | 524480 |
| 9 | 1928000 |
| 10 | 7206080 |
| 11 | 26535520 |
| 12 | 99030016 |
| 13 | 365153536 |
| 14 | 1361114752 |
| 15 | 5024242112 |
| 16 | 18709799552 |
| 17 | 69123162272 |
| 18 | 257205919680 |
| 19 | 950917193216 |
| 20 | 3536088581440 |
| 21 | 13080799664192 |
| 22 | 48617201294144 |
[16,256,704,2816,10144,38208,140032,524480, 1928000,7206080,26535520,99030016,365153536, 1361114752,5024242112,18709799552,69123162272, 257205919680,950917193216,3536088581440, 13080799664192,48617201294144] |