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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 60 |
| 5 | 217 |
| 6 | 798 |
| 7 | 2970 |
| 8 | 11154 |
| 9 | 42185 |
| 10 | 160446 |
| 11 | 613054 |
| 12 | 2351440 |
| 13 | 9048522 |
| 14 | 34916300 |
| 15 | 135059220 |
| 16 | 523521630 |
| 17 | 2033066025 |
| 18 | 7908332190 |
| 19 | 30807696150 |
| 20 | 120173896920 |
| 21 | 469334610030 |
| 22 | 1834970026500 |
[1,5,17,60,217,798,2970,11154,42185,160446,613054, 2351440,9048522,34916300,135059220,523521630, 2033066025,7908332190,30807696150,120173896920, 469334610030,1834970026500] |