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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 12 |
| 3 | 48 |
| 4 | 256 |
| 5 | 856 |
| 6 | 4096 |
| 7 | 15872 |
| 8 | 65344 |
| 9 | 259584 |
| 10 | 1048576 |
| 11 | 4177632 |
| 12 | 16777216 |
| 13 | 67051520 |
| 14 | 268430336 |
| 15 | 1073479680 |
| 16 | 4294967296 |
| 17 | 17178580480 |
| 18 | 68719476736 |
| 19 | 274872664064 |
| 20 | 1099511513088 |
| 21 | 4398023442432 |
| 22 | 17592186044416 |
| 23 | 70368641459200 |
[2,12,48,256,856,4096,15872,65344,259584,1048576, 4177632,16777216,67051520,268430336,1073479680, 4294967296,17178580480,68719476736,274872664064, 1099511513088,4398023442432,17592186044416, 70368641459200] |