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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 28 |
| 5 | 71 |
| 6 | 186 |
| 7 | 507 |
| 8 | 1443 |
| 9 | 4241 |
| 10 | 12895 |
| 11 | 40333 |
| 12 | 129679 |
| 13 | 427455 |
| 14 | 1442384 |
| 15 | 4975291 |
| 16 | 17518890 |
| 17 | 62907021 |
| 18 | 230104503 |
| 19 | 856679290 |
| 20 | 3243467627 |
| 21 | 12479244341 |
| 22 | 48759284806 |
| 23 | 193353224018 |
| 24 | 777721210211 |
[2,5,12,28,71,186,507,1443,4241,12895,40333, 129679,427455,1442384,4975291,17518890,62907021, 230104503,856679290,3243467627,12479244341, 48759284806,193353224018,777721210211] |