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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 15 |
| 4 | 47 |
| 5 | 150 |
| 6 | 511 |
| 7 | 1818 |
| 8 | 6553 |
| 9 | 24152 |
| 10 | 91011 |
| 11 | 345464 |
| 12 | 1323971 |
| 13 | 5153325 |
| 14 | 20242463 |
| 15 | 79980418 |
| 16 | 318692165 |
| 17 | 1278021945 |
| 18 | 5144043475 |
| 19 | 20816623561 |
| 20 | 84730346521 |
| 21 | 346195467540 |
| 22 | 1419588411167 |
| 23 | 5844061918042 |
| 24 | 24128251545872 |
| 25 | 99868971598520 |
| 26 | 414648751273051 |
| 27 | 1726489726795012 |
| 28 | 7204868556994227 |
[1,2,5,15,47,150,511,1818,6553,24152,91011,345464, 1323971,5153325,20242463,79980418,318692165, 1278021945,5144043475,20816623561,84730346521, 346195467540,1419588411167,5844061918042, 24128251545872,99868971598520,414648751273051, 1726489726795012,7204868556994227] |