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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 5 |
| 3 | 17 |
| 4 | 68 |
| 5 | 293 |
| 6 | 1310 |
| 7 | 5984 |
| 8 | 27725 |
| 9 | 129773 |
| 10 | 612158 |
| 11 | 2905322 |
| 12 | 13857035 |
| 13 | 66361892 |
| 14 | 318901523 |
| 15 | 1536964313 |
| 16 | 7426185908 |
| 17 | 35960185373 |
| 18 | 174468439958 |
| 19 | 847920579938 |
| 20 | 4127211830363 |
| 21 | 20116566452918 |
| 22 | 98172213841553 |
| 23 | 479635277636543 |
| 24 | 2345731259059238 |
| 25 | 11482918774964588 |
| 26 | 56260052353307435 |
| 27 | 275862429353287079 |
| 28 | 1353641461527506630 |
[2,5,17,68,293,1310,5984,27725,129773,612158, 2905322,13857035,66361892,318901523,1536964313, 7426185908,35960185373,174468439958,847920579938, 4127211830363,20116566452918,98172213841553, 479635277636543,2345731259059238, 11482918774964588,56260052353307435, 275862429353287079,1353641461527506630] |