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| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 4 |
| 3 | 14 |
| 4 | 17 |
| 5 | 93 |
| 6 | 379 |
| 7 | 2909 |
| 8 | 20374 |
| 9 | 121878 |
| 10 | 785046 |
| 11 | 3811314 |
| 12 | 20729459 |
| 13 | 86398810 |
| 14 | 401508982 |
| 15 | 1487808602 |
| 16 | 6052744740 |
| 17 | 20393912111 |
| 18 | 74234335758 |
| 19 | 230979488062 |
| 20 | 765576270536 |
| 21 | 2224840569660 |
| 22 | 6807977828585 |
| 23 | 18640043440258 |
| 24 | 53237097603882 |
[4,4,14,17,93,379,2909,20374,121878,785046, 3811314,20729459,86398810,401508982,1487808602, 6052744740,20393912111,74234335758,230979488062, 765576270536,2224840569660,6807977828585, 18640043440258,53237097603882] |