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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 24 |
| 3 | 96 |
| 4 | 288 |
| 5 | 1056 |
| 6 | 3360 |
| 7 | 11808 |
| 8 | 38688 |
| 9 | 133152 |
| 10 | 442656 |
| 11 | 1507872 |
| 12 | 5049120 |
| 13 | 17112096 |
| 14 | 57505056 |
| 15 | 194401824 |
| 16 | 654442272 |
| 17 | 2209656864 |
| 18 | 7445195040 |
| 19 | 25122449952 |
| 20 | 84684010272 |
| 21 | 285663609888 |
| 22 | 963135692064 |
| 23 | 3248444571168 |
| 24 | 10953530107680 |
[9,24,96,288,1056,3360,11808,38688,133152,442656, 1507872,5049120,17112096,57505056,194401824, 654442272,2209656864,7445195040,25122449952, 84684010272,285663609888,963135692064, 3248444571168,10953530107680] |