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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 32 |
| 3 | 132 |
| 4 | 576 |
| 5 | 2540 |
| 6 | 11112 |
| 7 | 48076 |
| 8 | 205952 |
| 9 | 875196 |
| 10 | 3695160 |
| 11 | 15519548 |
| 12 | 64899792 |
| 13 | 270415652 |
| 14 | 1123264856 |
| 15 | 4653525660 |
| 16 | 19234572544 |
| 17 | 79342611548 |
| 18 | 326704870872 |
| 19 | 1343120024476 |
| 20 | 5513861152880 |
| 21 | 22606830726564 |
| 22 | 92580354403768 |
| 23 | 378737813469692 |
| 24 | 1547884976788896 |
| 25 | 6320530321887700 |
| 26 | 25787763713301512 |
[2,32,132,576,2540,11112,48076,205952,875196, 3695160,15519548,64899792,270415652,1123264856, 4653525660,19234572544,79342611548,326704870872, 1343120024476,5513861152880,22606830726564, 92580354403768,378737813469692,1547884976788896, 6320530321887700,25787763713301512] |