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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 11 |
| 3 | 47 |
| 4 | 205 |
| 5 | 927 |
| 6 | 4237 |
| 7 | 19681 |
| 8 | 92309 |
| 9 | 436233 |
| 10 | 2073425 |
| 11 | 9901689 |
| 12 | 47489797 |
| 13 | 228532493 |
| 14 | 1102918479 |
| 15 | 5335687639 |
| 16 | 25869910029 |
| 17 | 125669892361 |
| 18 | 611494078813 |
| 19 | 2979843027241 |
| 20 | 14540339089485 |
| 21 | 71036575846341 |
| 22 | 347425556031339 |
| 23 | 1700858930851011 |
| 24 | 8334228174477185 |
| 25 | 40871697023737373 |
| 26 | 200590664206003375 |
[1,3,11,47,205,927,4237,19681,92309,436233, 2073425,9901689,47489797,228532493,1102918479, 5335687639,25869910029,125669892361,611494078813, 2979843027241,14540339089485,71036575846341, 347425556031339,1700858930851011,8334228174477185, 40871697023737373,200590664206003375] |