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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 104 |
| 3 | 618 |
| 4 | 2452 |
| 5 | 7803 |
| 6 | 22106 |
| 7 | 58005 |
| 8 | 144283 |
| 9 | 344972 |
| 10 | 800225 |
| 11 | 1812024 |
| 12 | 4023754 |
| 13 | 8791481 |
| 14 | 18948288 |
| 15 | 40366695 |
| 16 | 85135873 |
| 17 | 177990242 |
| 18 | 369259703 |
| 19 | 760850914 |
| 20 | 1558181104 |
| 21 | 3173635543 |
| 22 | 6432024694 |
| 23 | 12977428633 |
| 24 | 26076680087 |
| 25 | 52202242904 |
[2,104,618,2452,7803,22106,58005,144283,344972, 800225,1812024,4023754,8791481,18948288,40366695, 85135873,177990242,369259703,760850914,1558181104, 3173635543,6432024694,12977428633,26076680087, 52202242904] |