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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 17 |
| 5 | 39 |
| 6 | 89 |
| 7 | 203 |
| 8 | 459 |
| 9 | 1029 |
| 10 | 2299 |
| 11 | 5129 |
| 12 | 11409 |
| 13 | 25273 |
| 14 | 55787 |
| 15 | 122875 |
| 16 | 270239 |
| 17 | 593331 |
| 18 | 1299883 |
| 19 | 2841243 |
| 20 | 6197855 |
| 21 | 13499235 |
| 22 | 29366411 |
| 23 | 63809311 |
| 24 | 138466835 |
| 25 | 300036895 |
| 26 | 649186659 |
| 27 | 1402796793 |
| 28 | 3027908077 |
| 29 | 6529611587 |
| 30 | 14068804905 |
[1,3,7,17,39,89,203,459,1029,2299,5129,11409, 25273,55787,122875,270239,593331,1299883,2841243, 6197855,13499235,29366411,63809311,138466835, 300036895,649186659,1402796793,3027908077, 6529611587,14068804905] |