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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 45 |
| 4 | 194 |
| 5 | 870 |
| 6 | 3993 |
| 7 | 18631 |
| 8 | 88068 |
| 9 | 420149 |
| 10 | 2019374 |
| 11 | 9763410 |
| 12 | 47425833 |
| 13 | 231270952 |
| 14 | 1131400826 |
| 15 | 5549719306 |
| 16 | 27284114986 |
| 17 | 134394443468 |
| 18 | 663082316282 |
| 19 | 3276197809494 |
| 20 | 16207136789740 |
| 21 | 80261675763645 |
| 22 | 397848536171198 |
| 23 | 1973720814240814 |
| 24 | 9798743484589656 |
| 25 | 48678325970474082 |
| 26 | 241963833919074855 |
[1,3,11,45,194,870,3993,18631,88068,420149, 2019374,9763410,47425833,231270952,1131400826, 5549719306,27284114986,134394443468,663082316282, 3276197809494,16207136789740,80261675763645, 397848536171198,1973720814240814,9798743484589656, 48678325970474082,241963833919074855] |