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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 38 |
| 4 | 174 |
| 5 | 800 |
| 6 | 3798 |
| 7 | 18079 |
| 8 | 87274 |
| 9 | 422415 |
| 10 | 2059680 |
| 11 | 10064422 |
| 12 | 49389115 |
| 13 | 242777149 |
| 14 | 1196585692 |
| 15 | 5905460251 |
| 16 | 29196695458 |
| 17 | 144498323490 |
| 18 | 716025773879 |
| 19 | 3550975915698 |
| 20 | 17626078832477 |
| 21 | 87547432848604 |
| 22 | 435132850064506 |
| 23 | 2163832245029922 |
| 24 | 10765847763966771 |
| 25 | 53586144482555603 |
| 26 | 266827917734888510 |
[1,2,9,38,174,800,3798,18079,87274,422415,2059680, 10064422,49389115,242777149,1196585692,5905460251, 29196695458,144498323490,716025773879, 3550975915698,17626078832477,87547432848604, 435132850064506,2163832245029922, 10765847763966771,53586144482555603, 266827917734888510] |