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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 44 |
| 5 | 184 |
| 6 | 792 |
| 7 | 3484 |
| 8 | 15592 |
| 9 | 70745 |
| 10 | 324561 |
| 11 | 1502511 |
| 12 | 7007929 |
| 13 | 32892778 |
| 14 | 155221536 |
| 15 | 735915652 |
| 16 | 3503270920 |
| 17 | 16737092549 |
| 18 | 80218277681 |
| 19 | 385574074383 |
| 20 | 1858059853316 |
| 21 | 8974761939239 |
| 22 | 43441619693731 |
| 23 | 210682920968681 |
[1,3,11,44,184,792,3484,15592,70745,324561, 1502511,7007929,32892778,155221536,735915652, 3503270920,16737092549,80218277681,385574074383, 1858059853316,8974761939239,43441619693731, 210682920968681] |