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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 14 |
| 3 | 64 |
| 4 | 307 |
| 5 | 1485 |
| 6 | 7269 |
| 7 | 35755 |
| 8 | 176665 |
| 9 | 875277 |
| 10 | 4345792 |
| 11 | 21609460 |
| 12 | 107578587 |
| 13 | 536028717 |
| 14 | 2672677318 |
| 15 | 13333233492 |
| 16 | 66543700069 |
| 17 | 332218051799 |
| 18 | 1659035211312 |
| 19 | 8286699157204 |
| 20 | 41398391047875 |
| 21 | 206846040896581 |
| 22 | 1033621721279993 |
| 23 | 5165563569986093 |
| 24 | 25817143778058803 |
| 25 | 129040837679109879 |
[1,3,14,64,307,1485,7269,35755,176665,875277, 4345792,21609460,107578587,536028717,2672677318, 13333233492,66543700069,332218051799, 1659035211312,8286699157204,41398391047875, 206846040896581,1033621721279993,5165563569986093, 25817143778058803,129040837679109879] |