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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 49 |
| 5 | 202 |
| 6 | 1069 |
| 7 | 6470 |
| 8 | 48353 |
| 9 | 391058 |
| 10 | 3767029 |
| 11 | 37936318 |
| 12 | 445650385 |
| 13 | 5359634906 |
| 14 | 74198053661 |
| 15 | 1036667808758 |
| 16 | 16516851030721 |
| 17 | 262805595346210 |
| 18 | 4735033850606437 |
| 19 | 84510767762583662 |
| 20 | 1698609728377283441 |
[1,2,5,14,49,202,1069,6470,48353,391058,3767029, 37936318,445650385,5359634906,74198053661, 1036667808758,16516851030721,262805595346210, 4735033850606437,84510767762583662, 1698609728377283441] |