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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 15 |
| 5 | 45 |
| 6 | 105 |
| 7 | 315 |
| 8 | 1155 |
| 9 | 26325 |
| 10 | 33705 |
| 11 | 449295 |
| 12 | 1805475 |
| 13 | 10240425 |
| 14 | 13800465 |
| 15 | 16029405 |
| 16 | 16286445 |
| 17 | 21003885 |
| 18 | 32062485 |
| 19 | 132701205 |
| 20 | 594397485 |
| 21 | 815634435 |
| 22 | 29169504045 |
| 23 | 40833636525 |
| 24 | 295612416135 |
| 25 | 636988686495 |
| 26 | 660733931655 |
| 27 | 724387847085 |
| 28 | 740099543085 |
| 29 | 1707894294975 |
| 30 | 4439852974095 |
| 31 | 7454198513685 |
[1,3,9,15,45,105,315,1155,26325,33705,449295, 1805475,10240425,13800465,16029405,16286445, 21003885,32062485,132701205,594397485,815634435, 29169504045,40833636525,295612416135,636988686495, 660733931655,724387847085,740099543085, 1707894294975,4439852974095,7454198513685] |