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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 30 |
| 4 | 136 |
| 5 | 580 |
| 6 | 2753 |
| 7 | 12444 |
| 8 | 60241 |
| 9 | 280841 |
| 10 | 1374083 |
| 11 | 6526155 |
| 12 | 32135134 |
| 13 | 154489239 |
| 14 | 763821842 |
| 15 | 3703025640 |
| 16 | 18358658426 |
| 17 | 89543838530 |
| 18 | 444787699907 |
| 19 | 2179253032373 |
| 20 | 10839929560975 |
| 21 | 53294309035054 |
| 22 | 265366430999969 |
| 23 | 1308194109799558 |
| 24 | 6518921651047642 |
| 25 | 32205801829801516 |
| 26 | 160582826643012618 |
[1,2,8,30,136,580,2753,12444,60241,280841,1374083, 6526155,32135134,154489239,763821842,3703025640, 18358658426,89543838530,444787699907, 2179253032373,10839929560975,53294309035054, 265366430999969,1308194109799558,6518921651047642, 32205801829801516,160582826643012618] |