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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 21 |
| 3 | 115 |
| 4 | 329 |
| 5 | 2171 |
| 6 | 6821 |
| 7 | 24331 |
| 8 | 50579 |
| 9 | 79421 |
| 10 | 103729 |
| 11 | 226859 |
| 12 | 357769 |
| 13 | 704791 |
| 14 | 1092521 |
| 15 | 1224829 |
| 16 | 2048129 |
| 17 | 2247829 |
| 18 | 2685341 |
| 19 | 5177371 |
| 20 | 6967489 |
| 21 | 9393509 |
| 22 | 11089121 |
| 23 | 12648871 |
| 24 | 13651441 |
| 25 | 16974079 |
| 26 | 25153171 |
| 27 | 30663671 |
| 28 | 38272079 |
| 29 | 46267561 |
| 30 | 74617619 |
| 31 | 86937421 |
| 32 | 90517951 |
[4,21,115,329,2171,6821,24331,50579,79421,103729, 226859,357769,704791,1092521,1224829,2048129, 2247829,2685341,5177371,6967489,9393509,11089121, 12648871,13651441,16974079,25153171,30663671, 38272079,46267561,74617619,86937421,90517951] |