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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 11 |
| 4 | 47 |
| 5 | 143 |
| 6 | 577 |
| 7 | 2003 |
| 8 | 8189 |
| 9 | 29843 |
| 10 | 124731 |
| 11 | 468077 |
| 12 | 1982325 |
| 13 | 7615769 |
| 14 | 32504611 |
| 15 | 127166593 |
| 16 | 545613979 |
| 17 | 2165128349 |
| 18 | 9325666379 |
| 19 | 37427761149 |
| 20 | 161750060809 |
| 21 | 655060952797 |
| 22 | 2839806387621 |
| 23 | 11585998089283 |
| 24 | 50367957492719 |
| 25 | 206787708777655 |
| 26 | 901090052665549 |
| 27 | 3719799128226609 |
[1,1,5,11,47,143,577,2003,8189,29843,124731, 468077,1982325,7615769,32504611,127166593, 545613979,2165128349,9325666379,37427761149, 161750060809,655060952797,2839806387621, 11585998089283,50367957492719,206787708777655, 901090052665549,3719799128226609] |