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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 21 |
| 3 | 26 |
| 4 | 66 |
| 5 | 153 |
| 6 | 380 |
| 7 | 1090 |
| 8 | 3120 |
| 9 | 9130 |
| 10 | 28503 |
| 11 | 92139 |
| 12 | 306958 |
| 13 | 1051554 |
| 14 | 3668169 |
| 15 | 12963076 |
| 16 | 46237599 |
| 17 | 165941571 |
| 18 | 598016312 |
| 19 | 2161073292 |
| 20 | 7823738491 |
| 21 | 28358286582 |
| 22 | 102869586674 |
| 23 | 373350974508 |
| 24 | 1355483499654 |
| 25 | 4922288630695 |
| 26 | 17877323961313 |
[5,21,26,66,153,380,1090,3120,9130,28503,92139, 306958,1051554,3668169,12963076,46237599, 165941571,598016312,2161073292,7823738491, 28358286582,102869586674,373350974508, 1355483499654,4922288630695,17877323961313] |