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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 35 |
| 5 | 97 |
| 6 | 300 |
| 7 | 886 |
| 8 | 2884 |
| 9 | 9038 |
| 10 | 30119 |
| 11 | 97044 |
| 12 | 330178 |
| 13 | 1093187 |
| 14 | 3760857 |
| 15 | 12642484 |
| 16 | 44030988 |
| 17 | 150422819 |
| 18 | 527900140 |
| 19 | 1820782288 |
| 20 | 6438077940 |
| 21 | 22426049665 |
| 22 | 79685359338 |
| 23 | 279367999565 |
| 24 | 997882736275 |
| 25 | 3522643337418 |
[1,2,5,12,35,97,300,886,2884,9038,30119,97044, 330178,1093187,3760857,12642484,44030988, 150422819,527900140,1820782288,6438077940, 22426049665,79685359338,279367999565,997882736275, 3522643337418] |