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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 10 |
| 3 | 33 |
| 4 | 113 |
| 5 | 397 |
| 6 | 1431 |
| 7 | 5249 |
| 8 | 19514 |
| 9 | 73260 |
| 10 | 277100 |
| 11 | 1054248 |
| 12 | 4029859 |
| 13 | 15463765 |
| 14 | 59531725 |
| 15 | 229816430 |
| 16 | 889301153 |
| 17 | 3448417251 |
| 18 | 13396337155 |
| 19 | 52126461984 |
| 20 | 203124067675 |
| 21 | 792559645912 |
| 22 | 3096104725974 |
| 23 | 12107810534937 |
| 24 | 47395948167885 |
| 25 | 185697860476576 |
[1,3,10,33,113,397,1431,5249,19514,73260,277100, 1054248,4029859,15463765,59531725,229816430, 889301153,3448417251,13396337155,52126461984, 203124067675,792559645912,3096104725974, 12107810534937,47395948167885,185697860476576] |