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| n | a(n) |
|---|---|
| 1 | 90 |
| 2 | 177 |
| 3 | 361 |
| 4 | 715 |
| 5 | 1478 |
| 6 | 2969 |
| 7 | 6186 |
| 8 | 12534 |
| 9 | 26219 |
| 10 | 53487 |
| 11 | 112079 |
| 12 | 229756 |
| 13 | 481725 |
| 14 | 990964 |
| 15 | 2077526 |
| 16 | 4284777 |
| 17 | 8978859 |
| 18 | 18554317 |
| 19 | 38857870 |
| 20 | 80416809 |
| 21 | 168307678 |
| 22 | 348718298 |
| 23 | 729394343 |
| 24 | 1512628937 |
| 25 | 3162067127 |
| 26 | 6562395892 |
| 27 | 13711273601 |
[90,177,361,715,1478,2969,6186,12534,26219,53487, 112079,229756,481725,990964,2077526,4284777, 8978859,18554317,38857870,80416809,168307678, 348718298,729394343,1512628937,3162067127, 6562395892,13711273601] |