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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 14 |
| 3 | 68 |
| 4 | 203 |
| 5 | 476 |
| 6 | 1421 |
| 7 | 3293 |
| 8 | 7910 |
| 9 | 20060 |
| 10 | 39509 |
| 11 | 89324 |
| 12 | 206711 |
| 13 | 442907 |
| 14 | 803924 |
| 15 | 1722464 |
| 16 | 3198608 |
| 17 | 6820523 |
| 18 | 13434254 |
| 19 | 27901259 |
| 20 | 50222267 |
[2,14,68,203,476,1421,3293,7910,20060,39509,89324, 206711,442907,803924,1722464,3198608,6820523, 13434254,27901259,50222267] |