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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 6 |
| 2 | 23 |
| 3 | 86 |
| 4 | 321 |
| 5 | 1198 |
| 6 | 4471 |
| 7 | 16686 |
| 8 | 62273 |
| 9 | 232406 |
| 10 | 867351 |
| 11 | 3236998 |
| 12 | 12080641 |
| 13 | 45085566 |
| 14 | 168261623 |
| 15 | 627960926 |
| 16 | 2343582081 |
| 17 | 8746367398 |
| 18 | 32641887511 |
| 19 | 121821182646 |
| 20 | 454642843073 |
| 21 | 1696750189646 |
| 22 | 6332357915511 |
| 23 | 23632681472398 |
[1,6,23,86,321,1198,4471,16686,62273,232406, 867351,3236998,12080641,45085566,168261623, 627960926,2343582081,8746367398,32641887511, 121821182646,454642843073,1696750189646, 6332357915511,23632681472398] |