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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 47 |
| 5 | 193 |
| 6 | 869 |
| 7 | 3583 |
| 8 | 12399 |
| 9 | 51287 |
| 10 | 217551 |
| 11 | 867797 |
| 12 | 3274727 |
| 13 | 13099145 |
| 14 | 55568089 |
| 15 | 216651145 |
| 16 | 878354151 |
| 17 | 3609915051 |
| 18 | 13596245715 |
| 19 | 55617915013 |
| 20 | 220140920491 |
| 21 | 676614665133 |
| 22 | 2955537029341 |
| 23 | 11835711831601 |
| 24 | 48642769948139 |
[1,1,3,11,47,193,869,3583,12399,51287,217551, 867797,3274727,13099145,55568089,216651145, 878354151,3609915051,13596245715,55617915013, 220140920491,676614665133,2955537029341, 11835711831601,48642769948139] |