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| n | a(n) |
|---|---|
| 1 | 24 |
| 2 | 116 |
| 3 | 556 |
| 4 | 2652 |
| 5 | 12588 |
| 6 | 59484 |
| 7 | 279932 |
| 8 | 1312364 |
| 9 | 6131052 |
| 10 | 28550492 |
| 11 | 132555868 |
| 12 | 613748556 |
| 13 | 2834515596 |
| 14 | 13060107900 |
| 15 | 60044009084 |
| 16 | 275496757868 |
| 17 | 1261682707500 |
| 18 | 5768039837468 |
| 19 | 26327131807900 |
| 20 | 119984300243340 |
| 21 | 546053643671244 |
[24,116,556,2652,12588,59484,279932,1312364, 6131052,28550492,132555868,613748556,2834515596, 13060107900,60044009084,275496757868, 1261682707500,5768039837468,26327131807900, 119984300243340,546053643671244] |