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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 12 |
| 4 | 24 |
| 5 | 64 |
| 6 | 184 |
| 7 | 432 |
| 8 | 1088 |
| 9 | 2944 |
| 10 | 7360 |
| 11 | 18496 |
| 12 | 48384 |
| 13 | 123392 |
| 14 | 312320 |
| 15 | 804864 |
| 16 | 2061824 |
| 17 | 5248000 |
| 18 | 13449216 |
| 19 | 34455552 |
| 20 | 87961600 |
| 21 | 225038336 |
| 22 | 576143360 |
| 23 | 1472741376 |
| 24 | 3766452224 |
| 25 | 9638051840 |
| 26 | 24648581120 |
| 27 | 63037702144 |
| 28 | 161266270208 |
[2,4,12,24,64,184,432,1088,2944,7360,18496,48384, 123392,312320,804864,2061824,5248000,13449216, 34455552,87961600,225038336,576143360,1472741376, 3766452224,9638051840,24648581120,63037702144, 161266270208] |