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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 38 |
| 4 | 185 |
| 5 | 922 |
| 6 | 4689 |
| 7 | 23998 |
| 8 | 123217 |
| 9 | 633458 |
| 10 | 3258489 |
| 11 | 16765718 |
| 12 | 86273225 |
| 13 | 443967370 |
| 14 | 2284733313 |
| 15 | 11757749038 |
| 16 | 60508271137 |
| 17 | 311391065570 |
| 18 | 1602499602537 |
| 19 | 8246883961094 |
| 20 | 42440638964825 |
| 21 | 218410733951098 |
| 22 | 1123999345270833 |
| 23 | 5784397706237854 |
[1,2,9,38,185,922,4689,23998,123217,633458, 3258489,16765718,86273225,443967370,2284733313, 11757749038,60508271137,311391065570, 1602499602537,8246883961094,42440638964825, 218410733951098,1123999345270833,5784397706237854] |