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| n | a(n) |
|---|---|
| 1 | 16 |
| 2 | 48 |
| 3 | 128 |
| 4 | 322 |
| 5 | 780 |
| 6 | 1874 |
| 7 | 4400 |
| 8 | 10458 |
| 9 | 24332 |
| 10 | 57922 |
| 11 | 134744 |
| 12 | 322650 |
| 13 | 753100 |
| 14 | 1815874 |
| 15 | 4256984 |
| 16 | 10332338 |
| 17 | 24326116 |
| 18 | 59383402 |
| 19 | 140337800 |
| 20 | 344230370 |
| 21 | 816065860 |
| 22 | 2009539410 |
| 23 | 4776207920 |
| 24 | 11798294714 |
| 25 | 28099290420 |
| 26 | 69585826082 |
[16,48,128,322,780,1874,4400,10458,24332,57922, 134744,322650,753100,1815874,4256984,10332338, 24326116,59383402,140337800,344230370,816065860, 2009539410,4776207920,11798294714,28099290420, 69585826082] |