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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 36 |
| 4 | 197 |
| 5 | 1184 |
| 6 | 7425 |
| 7 | 48308 |
| 8 | 322521 |
| 9 | 2198064 |
| 10 | 15227850 |
| 11 | 106924154 |
| 12 | 759245463 |
| 13 | 5442675080 |
| 14 | 39335090088 |
| 15 | 286296369000 |
| 16 | 2096706604597 |
| 17 | 15439417451928 |
| 18 | 114243931954962 |
| 19 | 849030345258990 |
| 20 | 6334510149389409 |
| 21 | 47428709540589036 |
| 22 | 356261301882333885 |
[1,2,7,36,197,1184,7425,48308,322521,2198064, 15227850,106924154,759245463,5442675080, 39335090088,286296369000,2096706604597, 15439417451928,114243931954962,849030345258990, 6334510149389409,47428709540589036, 356261301882333885] |