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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 23 |
| 3 | 88 |
| 4 | 495 |
| 5 | 2255 |
| 6 | 10934 |
| 7 | 54081 |
| 8 | 264797 |
| 9 | 1296124 |
| 10 | 6337697 |
| 11 | 31018085 |
| 12 | 151848926 |
| 13 | 743248211 |
| 14 | 3637769547 |
| 15 | 17804967270 |
| 16 | 87147406785 |
| 17 | 426548340739 |
| 18 | 2087759457552 |
| 19 | 10218622797201 |
| 20 | 50015488523633 |
| 21 | 244803024488552 |
| 22 | 1198199184277771 |
[3,23,88,495,2255,10934,54081,264797,1296124, 6337697,31018085,151848926,743248211,3637769547, 17804967270,87147406785,426548340739, 2087759457552,10218622797201,50015488523633, 244803024488552,1198199184277771] |