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| n | a(n) |
|---|---|
| 5 | 1 |
| 6 | 3 |
| 7 | 9 |
| 8 | 31 |
| 9 | 105 |
| 10 | 355 |
| 11 | 1198 |
| 12 | 4024 |
| 13 | 13429 |
| 14 | 44479 |
| 15 | 146145 |
| 16 | 476347 |
| 17 | 1540615 |
| 18 | 4946425 |
| 19 | 15774197 |
| 20 | 49992571 |
| 21 | 157545775 |
| 22 | 493946713 |
| 23 | 1541481630 |
| 24 | 4790452228 |
| 25 | 14831036177 |
| 26 | 45759663403 |
| 27 | 140751744489 |
| 28 | 431730577935 |
| 29 | 1320914941797 |
[1,3,9,31,105,355,1198,4024,13429,44479,146145, 476347,1540615,4946425,15774197,49992571, 157545775,493946713,1541481630,4790452228, 14831036177,45759663403,140751744489,431730577935, 1320914941797] |