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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 16 |
| 3 | 48 |
| 4 | 133 |
| 5 | 357 |
| 6 | 932 |
| 7 | 2392 |
| 8 | 6057 |
| 9 | 15189 |
| 10 | 37800 |
| 11 | 93520 |
| 12 | 230301 |
| 13 | 565045 |
| 14 | 1382236 |
| 15 | 3373208 |
| 16 | 8216033 |
| 17 | 19980037 |
| 18 | 48525632 |
| 19 | 117730352 |
| 20 | 285384437 |
| 21 | 691295429 |
| 22 | 1673567700 |
| 23 | 4049615640 |
| 24 | 9795168601 |
| 25 | 23684692085 |
| 26 | 57254031256 |
[1,5,16,48,133,357,932,2392,6057,15189,37800, 93520,230301,565045,1382236,3373208,8216033, 19980037,48525632,117730352,285384437,691295429, 1673567700,4049615640,9795168601,23684692085, 57254031256] |