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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 45 |
| 3 | 103 |
| 4 | 370 |
| 5 | 1318 |
| 6 | 4449 |
| 7 | 16187 |
| 8 | 57097 |
| 9 | 204138 |
| 10 | 731990 |
| 11 | 2619348 |
| 12 | 9409831 |
| 13 | 33795414 |
| 14 | 121433334 |
| 15 | 436597037 |
| 16 | 1569707036 |
| 17 | 5644843684 |
| 18 | 20301268685 |
| 19 | 73014988681 |
| 20 | 262618746090 |
| 21 | 944600144394 |
| 22 | 3397648654668 |
| 23 | 12221222404734 |
[2,45,103,370,1318,4449,16187,57097,204138,731990, 2619348,9409831,33795414,121433334,436597037, 1569707036,5644843684,20301268685,73014988681, 262618746090,944600144394,3397648654668, 12221222404734] |