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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 11 |
| 4 | 28 |
| 5 | 189 |
| 6 | 494 |
| 7 | 3383 |
| 8 | 8856 |
| 9 | 60697 |
| 10 | 158906 |
| 11 | 1089155 |
| 12 | 2851444 |
| 13 | 19544085 |
| 14 | 51167078 |
| 15 | 350704367 |
| 16 | 918155952 |
| 17 | 6293134513 |
| 18 | 16475640050 |
| 19 | 112925716859 |
| 20 | 295643364940 |
| 21 | 2026369768941 |
| 22 | 5305104928862 |
| 23 | 36361730124071 |
| 24 | 95196245354568 |
| 25 | 652484772464329 |
[1,2,11,28,189,494,3383,8856,60697,158906,1089155, 2851444,19544085,51167078,350704367,918155952, 6293134513,16475640050,112925716859,295643364940, 2026369768941,5305104928862,36361730124071, 95196245354568,652484772464329] |