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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 10 |
| 2 | 26 |
| 3 | 58 |
| 4 | 122 |
| 5 | 1146 |
| 6 | 5242 |
| 7 | 13434 |
| 8 | 46202 |
| 9 | 177274 |
| 10 | 701562 |
| 11 | 1750138 |
| 12 | 18527354 |
| 13 | 52081786 |
| 14 | 186299514 |
| 15 | 454734970 |
| 16 | 4749702266 |
| 17 | 21929571450 |
| 18 | 56289309818 |
| 19 | 331167216762 |
| 20 | 880923030650 |
| 21 | 1980434658426 |
| 22 | 6378481169530 |
| 23 | 15174574191738 |
[2,10,26,58,122,1146,5242,13434,46202,177274, 701562,1750138,18527354,52081786,186299514, 454734970,4749702266,21929571450,56289309818, 331167216762,880923030650,1980434658426, 6378481169530,15174574191738] |