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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 24 |
| 4 | 112 |
| 5 | 400 |
| 6 | 1888 |
| 7 | 7168 |
| 8 | 34816 |
| 9 | 139008 |
| 10 | 676864 |
| 11 | 2770944 |
| 12 | 13638656 |
| 13 | 57175040 |
| 14 | 281647104 |
| 15 | 1197072384 |
| 16 | 5927944192 |
| 17 | 25544916992 |
| 18 | 126540709888 |
| 19 | 550109839360 |
| 20 | 2733108625408 |
| 21 | 11989026865152 |
| 22 | 59573759639552 |
| 23 | 262935378132992 |
| 24 | 1308894989123584 |
| 25 | 5813681709383680 |
| 26 | 28942591693160448 |
| 27 | 129140161026981888 |
[1,2,8,24,112,400,1888,7168,34816,139008,676864, 2770944,13638656,57175040,281647104,1197072384, 5927944192,25544916992,126540709888,550109839360, 2733108625408,11989026865152,59573759639552, 262935378132992,1308894989123584,5813681709383680, 28942591693160448,129140161026981888] |