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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 31 |
| 6 | 114 |
| 7 | 454 |
| 8 | 2078 |
| 9 | 10168 |
| 10 | 53045 |
| 11 | 288037 |
| 12 | 1617483 |
| 13 | 9311503 |
| 14 | 54723397 |
| 15 | 327065591 |
| 16 | 1982926671 |
| 17 | 12169747393 |
| 18 | 75486178107 |
| 19 | 472601737413 |
| 20 | 2983335066047 |
| 21 | 18971431861215 |
| 22 | 121440495203940 |
| 23 | 782013670584330 |
| 24 | 5063068510021079 |
| 25 | 32942387619476871 |
| 26 | 215306810250387250 |
[1,2,4,11,31,114,454,2078,10168,53045,288037, 1617483,9311503,54723397,327065591,1982926671, 12169747393,75486178107,472601737413, 2983335066047,18971431861215,121440495203940, 782013670584330,5063068510021079, 32942387619476871,215306810250387250] |