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| n | a(n) |
|---|---|
| 0 | 6 |
| 1 | 21 |
| 2 | 62 |
| 3 | 168 |
| 4 | 426 |
| 5 | 1029 |
| 6 | 2394 |
| 7 | 5403 |
| 8 | 11892 |
| 9 | 25626 |
| 10 | 54228 |
| 11 | 112958 |
| 12 | 232056 |
| 13 | 470904 |
| 14 | 945152 |
| 15 | 1878351 |
| 16 | 3699666 |
| 17 | 7227807 |
| 18 | 14015538 |
| 19 | 26991978 |
| 20 | 51654946 |
| 21 | 98275461 |
| 22 | 185958162 |
| 23 | 350093468 |
| 24 | 655988730 |
| 25 | 1223722623 |
| 26 | 2273327418 |
| 27 | 4206691146 |
| 28 | 7755620994 |
| 29 | 14248825833 |
[6,21,62,168,426,1029,2394,5403,11892,25626,54228, 112958,232056,470904,945152,1878351,3699666, 7227807,14015538,26991978,51654946,98275461, 185958162,350093468,655988730,1223722623, 2273327418,4206691146,7755620994,14248825833] |