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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 7 |
| 3 | 15 |
| 4 | 33 |
| 5 | 75 |
| 6 | 167 |
| 7 | 361 |
| 8 | 791 |
| 9 | 1773 |
| 10 | 3931 |
| 11 | 8539 |
| 12 | 18737 |
| 13 | 41853 |
| 14 | 92693 |
| 15 | 201871 |
| 16 | 443343 |
| 17 | 988491 |
| 18 | 2187965 |
| 19 | 4772629 |
| 20 | 10487105 |
| 21 | 23354405 |
| 22 | 51673669 |
| 23 | 112840057 |
| 24 | 248040133 |
| 25 | 551900067 |
| 26 | 1220786323 |
| 27 | 2668013885 |
| 28 | 5866328943 |
[1,3,7,15,33,75,167,361,791,1773,3931,8539,18737, 41853,92693,201871,443343,988491,2187965,4772629, 10487105,23354405,51673669,112840057,248040133, 551900067,1220786323,2668013885,5866328943] |