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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 5 |
| 3 | 13 |
| 4 | 23 |
| 5 | 53 |
| 6 | 131 |
| 7 | 330 |
| 8 | 793 |
| 9 | 1930 |
| 10 | 4765 |
| 11 | 11686 |
| 12 | 28627 |
| 13 | 70237 |
| 14 | 172374 |
| 15 | 422930 |
| 16 | 1037573 |
| 17 | 2545757 |
| 18 | 6246392 |
| 19 | 15325889 |
| 20 | 37602947 |
| 21 | 92261907 |
| 22 | 226372036 |
| 23 | 555420895 |
| 24 | 1362767425 |
| 25 | 3343655704 |
| 26 | 8203918429 |
| 27 | 20128946224 |
| 28 | 49387923264 |
| 29 | 121177087505 |
[4,5,13,23,53,131,330,793,1930,4765,11686,28627, 70237,172374,422930,1037573,2545757,6246392, 15325889,37602947,92261907,226372036,555420895, 1362767425,3343655704,8203918429,20128946224, 49387923264,121177087505] |